diff --git a/bin/list_products b/bin/list_products
new file mode 100755
index 0000000..cd8dd5c
--- /dev/null
+++ b/bin/list_products
@@ -0,0 +1,32 @@
+#!/bin/bash
+
+# Copyright (C) 2024 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Common script utilities
+source $(cd $(dirname $BASH_SOURCE) &> /dev/null && pwd)/../../make/shell_utils.sh
+
+require_top
+
+# In almost call cases including get_build_var, TARGET_RELEASE is required,
+# but the list of available products is not dependent on the release config
+# (but note that the list of available release configs is dependent on the
+# product). So for list_products, we'll just set it to trunk_staging, which
+# exists everwhere, so we don't trigger the unspecified TARGET_RELEASE error.
+
+# We also unset TARGET_BUILD_APPS, so it doesn't interfere.
+
+TARGET_RELEASE=trunk_staging TARGET_BUILD_APPS= $TOP/build/soong/soong_ui.bash --dumpvar-mode all_named_products | sed 's/ /\n/g'
+
+exit $?
diff --git a/bin/list_releases b/bin/list_releases
new file mode 100755
index 0000000..ca18110
--- /dev/null
+++ b/bin/list_releases
@@ -0,0 +1,45 @@
+#!/bin/bash
+
+# Copyright (C) 2024 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+if [[ $# -eq 1 ]]; then
+    # Override anything that's already set
+    export TARGET_PRODUCT=$1
+elif [[ -z $TARGET_PRODUCT ]]; then
+    echo "Usage: list_releases [PRODUCT]" 1>&2
+    echo "" 1>&2
+    echo "If the optional PRODUCT parameter is bit provided, then TARGET_PRODUCT" 1>&2
+    echo "must have been set, for example by lunch or banchan." 1>&2
+    exit 1
+fi
+
+
+
+# Common script utilities
+source $(cd $(dirname $BASH_SOURCE) &> /dev/null && pwd)/../../make/shell_utils.sh
+
+require_top
+
+# In almost call cases including get_build_var, TARGET_RELEASE is required,
+# but the list of available products is not dependent on the release config
+# (but note that the list of available release configs is dependent on the
+# product). So for list_products, we'll just set it to trunk_staging, which
+# exists everwhere, so we don't trigger the unspecified TARGET_RELEASE error.
+
+# We also unset TARGET_BUILD_APPS, so it doesn't interfere.
+
+TARGET_RELEASE=trunk_staging TARGET_BUILD_APPS= $TOP/build/soong/soong_ui.bash --dumpvar-mode ALL_RELEASE_CONFIGS_FOR_PRODUCT | sed 's/ /\n/g'
+
+exit $?
diff --git a/bin/list_variants b/bin/list_variants
new file mode 100755
index 0000000..ac89e6a
--- /dev/null
+++ b/bin/list_variants
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# Copyright (C) 2024 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+echo user
+echo userdebug
+echo eng
+
diff --git a/cmd/release_config/release_config_lib/release_config.go b/cmd/release_config/release_config_lib/release_config.go
index 4643053..02b693c 100644
--- a/cmd/release_config/release_config_lib/release_config.go
+++ b/cmd/release_config/release_config_lib/release_config.go
@@ -81,6 +81,10 @@
 
 	// Partitioned artifacts for {partition}/etc/build_flags.json
 	PartitionBuildFlags map[string]*rc_proto.FlagArtifacts
+
+	// Prior stage(s) for flag advancement (during development).
+	// Once a flag has met criteria in a prior stage, it can advance to this one.
+	PriorStagesMap map[string]bool
 }
 
 func ReleaseConfigFactory(name string, index int) (c *ReleaseConfig) {
@@ -88,6 +92,7 @@
 		Name:             name,
 		DeclarationIndex: index,
 		FilesUsedMap:     make(map[string]bool),
+		PriorStagesMap:   make(map[string]bool),
 	}
 }
 
@@ -118,14 +123,7 @@
 }
 
 func (config *ReleaseConfig) GetSortedFileList() []string {
-	ret := []string{}
-	for k := range config.FilesUsedMap {
-		ret = append(ret, k)
-	}
-	slices.SortFunc(ret, func(a, b string) int {
-		return cmp.Compare(a, b)
-	})
-	return ret
+	return SortedMapKeys(config.FilesUsedMap)
 }
 
 func (config *ReleaseConfig) GenerateReleaseConfig(configs *ReleaseConfigs) error {
@@ -162,6 +160,9 @@
 		if _, ok := myInheritsSet[inherit]; ok {
 			continue
 		}
+		if isBuildPrefix && configs.Aliases[inherit] != nil {
+			return fmt.Errorf("%s cannot inherit from alias %s", config.Name, inherit)
+		}
 		myInherits = append(myInherits, inherit)
 		myInheritsSet[inherit] = true
 		iConfig, err := configs.GetReleaseConfig(inherit)
@@ -216,6 +217,9 @@
 				Value:  &rc_proto.Value{Val: &rc_proto.Value_StringValue{contribAconfigValueSetsString}},
 			})
 
+		for _, priorStage := range contrib.proto.PriorStages {
+			config.PriorStagesMap[priorStage] = true
+		}
 		myDirsMap[contrib.DeclarationIndex] = true
 		if config.AconfigFlagsOnly && len(contrib.FlagValues) > 0 {
 			return fmt.Errorf("%s does not allow build flag overrides", config.Name)
@@ -299,6 +303,7 @@
 		AconfigValueSets: myAconfigValueSets,
 		Inherits:         myInherits,
 		Directories:      directories,
+		PriorStages:      SortedMapKeys(config.PriorStagesMap),
 	}
 
 	config.compileInProgress = false
diff --git a/cmd/release_config/release_config_lib/release_configs.go b/cmd/release_config/release_config_lib/release_configs.go
index bad9144..4b4e355 100644
--- a/cmd/release_config/release_config_lib/release_configs.go
+++ b/cmd/release_config/release_config_lib/release_configs.go
@@ -79,13 +79,11 @@
 }
 
 func (configs *ReleaseConfigs) WriteInheritanceGraph(outFile string) error {
-	data := []string{
-		"digraph {",
-		"graph [ ratio=.5 ]",
-		"node [ shape=box style=filled fillcolor=white colorscheme=svg fontcolor=black ]",
-	}
+	data := []string{}
 	usedAliases := make(map[string]bool)
-	for _, config := range configs.GetSortedReleaseConfigs() {
+	priorStages := make(map[string][]string)
+	rankedStageNames := make(map[string]bool)
+	for _, config := range configs.ReleaseConfigs {
 		var fillColor string
 		inherits := []string{}
 		for _, inherit := range config.InheritNames {
@@ -108,6 +106,17 @@
 				}
 			}
 		}
+		// Add links for all of the advancement progressions.
+		for priorStage := range config.PriorStagesMap {
+			stageName := config.Name
+			if len(config.OtherNames) > 0 {
+				stageName = config.OtherNames[0]
+			}
+			data = append(data, fmt.Sprintf(`"%s" -> "%s" [ style=dashed color="#81c995" ]`,
+				priorStage, stageName))
+			priorStages[stageName] = append(priorStages[stageName], priorStage)
+			rankedStageNames[stageName] = true
+		}
 		label := config.Name
 		if len(inherits) > 0 {
 			label += "\\ninherits: " + strings.Join(inherits, " ")
@@ -122,6 +131,15 @@
 		data = append(data,
 			fmt.Sprintf(`"%s" [ label="%s" %s]`, config.Name, label, fillColor))
 	}
+	if len(rankedStageNames) > 0 {
+		data = append(data, fmt.Sprintf("subgraph {rank=same %s}", strings.Join(SortedMapKeys(rankedStageNames), " ")))
+	}
+	slices.Sort(data)
+	data = append([]string{
+		"digraph {",
+		"graph [ ratio=.5 ]",
+		"node [ shape=box style=filled fillcolor=white colorscheme=svg fontcolor=black ]",
+	}, data...)
 	data = append(data, "}")
 	return os.WriteFile(outFile, []byte(strings.Join(data, "\n")), 0644)
 }
@@ -436,8 +454,8 @@
 	if targetRelease != config.Name {
 		data += fmt.Sprintf("# User specified TARGET_RELEASE=%s\n", targetRelease)
 	}
-	// The variable _all_release_configs will get deleted during processing, so do not mark it read-only.
-	data += fmt.Sprintf("_all_release_configs := %s\n", strings.Join(configs.GetAllReleaseNames(), " "))
+	// As it stands this list is not per-product, but conceptually it is, and will be.
+	data += fmt.Sprintf("ALL_RELEASE_CONFIGS_FOR_PRODUCT :=$= %s\n", strings.Join(configs.GetAllReleaseNames(), " "))
 	data += fmt.Sprintf("_used_files := %s\n", strings.Join(config.GetSortedFileList(), " "))
 	data += fmt.Sprintf("_ALL_RELEASE_FLAGS :=$= %s\n", strings.Join(names, " "))
 	for _, pName := range pNames {
diff --git a/cmd/release_config/release_config_lib/util.go b/cmd/release_config/release_config_lib/util.go
index 0af99a6..b8824d1 100644
--- a/cmd/release_config/release_config_lib/util.go
+++ b/cmd/release_config/release_config_lib/util.go
@@ -22,6 +22,7 @@
 	"os/exec"
 	"path/filepath"
 	"regexp"
+	"slices"
 	"strings"
 
 	"google.golang.org/protobuf/encoding/prototext"
@@ -159,6 +160,15 @@
 	return 0, nil
 }
 
+func SortedMapKeys(inputMap map[string]bool) []string {
+	ret := []string{}
+	for k := range inputMap {
+		ret = append(ret, k)
+	}
+	slices.Sort(ret)
+	return ret
+}
+
 func validContainer(container string) bool {
 	return containerRegexp.MatchString(container)
 }
diff --git a/cmd/release_config/release_config_proto/build_flags_out.pb.go b/cmd/release_config/release_config_proto/build_flags_out.pb.go
index 42ae6f9..309ec34 100644
--- a/cmd/release_config/release_config_proto/build_flags_out.pb.go
+++ b/cmd/release_config/release_config_proto/build_flags_out.pb.go
@@ -226,6 +226,9 @@
 	// The release config directories used for this config.
 	// For example, "build/release".
 	Directories []string `protobuf:"bytes,6,rep,name=directories" json:"directories,omitempty"`
+	// Prior stage(s) for flag advancement (during development).
+	// Once a flag has met criteria in a prior stage, it can advance to this one.
+	PriorStages []string `protobuf:"bytes,7,rep,name=prior_stages,json=priorStages" json:"prior_stages,omitempty"`
 }
 
 func (x *ReleaseConfigArtifact) Reset() {
@@ -302,6 +305,13 @@
 	return nil
 }
 
+func (x *ReleaseConfigArtifact) GetPriorStages() []string {
+	if x != nil {
+		return x.PriorStages
+	}
+	return nil
+}
+
 type ReleaseConfigsArtifact struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -403,7 +413,7 @@
 	0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x70, 0x72, 0x6f,
 	0x74, 0x6f, 0x2e, 0x66, 0x6c, 0x61, 0x67, 0x5f, 0x61, 0x72, 0x74, 0x69, 0x66, 0x61, 0x63, 0x74,
 	0x52, 0x0d, 0x66, 0x6c, 0x61, 0x67, 0x41, 0x72, 0x74, 0x69, 0x66, 0x61, 0x63, 0x74, 0x73, 0x22,
-	0x8e, 0x02, 0x0a, 0x17, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66,
+	0xb1, 0x02, 0x0a, 0x17, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66,
 	0x69, 0x67, 0x5f, 0x61, 0x72, 0x74, 0x69, 0x66, 0x61, 0x63, 0x74, 0x12, 0x12, 0x0a, 0x04, 0x6e,
 	0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x12,
 	0x1f, 0x0a, 0x0b, 0x6f, 0x74, 0x68, 0x65, 0x72, 0x5f, 0x6e, 0x61, 0x6d, 0x65, 0x73, 0x18, 0x02,
@@ -420,40 +430,43 @@
 	0x20, 0x03, 0x28, 0x09, 0x52, 0x08, 0x69, 0x6e, 0x68, 0x65, 0x72, 0x69, 0x74, 0x73, 0x12, 0x20,
 	0x0a, 0x0b, 0x64, 0x69, 0x72, 0x65, 0x63, 0x74, 0x6f, 0x72, 0x69, 0x65, 0x73, 0x18, 0x06, 0x20,
 	0x03, 0x28, 0x09, 0x52, 0x0b, 0x64, 0x69, 0x72, 0x65, 0x63, 0x74, 0x6f, 0x72, 0x69, 0x65, 0x73,
-	0x22, 0xe8, 0x03, 0x0a, 0x18, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e,
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+	0x6f, 0x74, 0x6f,
 }
 
 var (
diff --git a/cmd/release_config/release_config_proto/build_flags_out.proto b/cmd/release_config/release_config_proto/build_flags_out.proto
index 8c3be5f..0cbc157 100644
--- a/cmd/release_config/release_config_proto/build_flags_out.proto
+++ b/cmd/release_config/release_config_proto/build_flags_out.proto
@@ -83,6 +83,10 @@
   // The release config directories used for this config.
   // For example, "build/release".
   repeated string directories = 6;
+
+  // Prior stage(s) for flag advancement (during development).
+  // Once a flag has met criteria in a prior stage, it can advance to this one.
+  repeated string prior_stages = 7;
 }
 
 message release_configs_artifact {
diff --git a/cmd/release_config/release_config_proto/build_flags_src.pb.go b/cmd/release_config/release_config_proto/build_flags_src.pb.go
index 1b63961..8de340e 100644
--- a/cmd/release_config/release_config_proto/build_flags_src.pb.go
+++ b/cmd/release_config/release_config_proto/build_flags_src.pb.go
@@ -326,6 +326,9 @@
 	AconfigValueSets []string `protobuf:"bytes,3,rep,name=aconfig_value_sets,json=aconfigValueSets" json:"aconfig_value_sets,omitempty"`
 	// Only aconfig flags are allowed in this release config.
 	AconfigFlagsOnly *bool `protobuf:"varint,4,opt,name=aconfig_flags_only,json=aconfigFlagsOnly" json:"aconfig_flags_only,omitempty"`
+	// Prior stage(s) for flag advancement (during development).
+	// Once a flag has met criteria in a prior stage, it can advance to this one.
+	PriorStages []string `protobuf:"bytes,5,rep,name=prior_stages,json=priorStages" json:"prior_stages,omitempty"`
 }
 
 func (x *ReleaseConfig) Reset() {
@@ -388,6 +391,13 @@
 	return false
 }
 
+func (x *ReleaseConfig) GetPriorStages() []string {
+	if x != nil {
+		return x.PriorStages
+	}
+	return nil
+}
+
 // Any aliases.  These are used for continuous integration builder config.
 type ReleaseAlias struct {
 	state         protoimpl.MessageState
@@ -556,7 +566,7 @@
 	0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x70, 0x72, 0x6f, 0x74,
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 	0x0a, 0x08, 0x72, 0x65, 0x64, 0x61, 0x63, 0x74, 0x65, 0x64, 0x18, 0xca, 0x01, 0x20, 0x01, 0x28,
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+	0x08, 0x52, 0x08, 0x72, 0x65, 0x64, 0x61, 0x63, 0x74, 0x65, 0x64, 0x22, 0xbf, 0x01, 0x0a, 0x0e,
 	0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x12, 0x12,
 	0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x04, 0x6e, 0x61,
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@@ -566,25 +576,27 @@
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 }
 
 var (
diff --git a/cmd/release_config/release_config_proto/build_flags_src.proto b/cmd/release_config/release_config_proto/build_flags_src.proto
index 6623294..4fad478 100644
--- a/cmd/release_config/release_config_proto/build_flags_src.proto
+++ b/cmd/release_config/release_config_proto/build_flags_src.proto
@@ -113,6 +113,10 @@
 
   // Only aconfig flags are allowed in this release config.
   optional bool aconfig_flags_only = 4;
+
+  // Prior stage(s) for flag advancement (during development).
+  // Once a flag has met criteria in a prior stage, it can advance to this one.
+  repeated string prior_stages = 5;
 }
 
 // Any aliases.  These are used for continuous integration builder config.
diff --git a/java/droidstubs.go b/java/droidstubs.go
index b94ad16..5ca6c25 100644
--- a/java/droidstubs.go
+++ b/java/droidstubs.go
@@ -1153,6 +1153,9 @@
 		}
 	}
 
+	// Treat documentation issues as warnings, but error when new.
+	cmd.Flag("--error-when-new-category").Flag("Documentation")
+
 	if params.stubConfig.generateStubs {
 		rule.Command().
 			BuiltTool("soong_zip").