diff --git a/fastboot/device/flashing.cpp b/fastboot/device/flashing.cpp
index 66b90bf..7c9e1d0 100644
--- a/fastboot/device/flashing.cpp
+++ b/fastboot/device/flashing.cpp
@@ -148,13 +148,40 @@
     // image.
     std::string slot_suffix = device->GetCurrentSlot();
     uint32_t slot_number = SlotNumberForSlotSuffix(slot_suffix);
-    if (wipe || !ReadMetadata(super_name, slot_number)) {
+    std::unique_ptr<LpMetadata> old_metadata = ReadMetadata(super_name, slot_number);
+    if (wipe || !old_metadata) {
         if (!FlashPartitionTable(super_name, *new_metadata.get())) {
             return device->WriteFail("Unable to flash new partition table");
         }
         return device->WriteOkay("Successfully flashed partition table");
     }
 
+    std::set<std::string> partitions_to_keep;
+    for (const auto& partition : old_metadata->partitions) {
+        // Preserve partitions in the other slot, but not the current slot.
+        std::string partition_name = GetPartitionName(partition);
+        if (!slot_suffix.empty() && GetPartitionSlotSuffix(partition_name) == slot_suffix) {
+            continue;
+        }
+        partitions_to_keep.emplace(partition_name);
+    }
+
+    // Do not preserve the scratch partition.
+    partitions_to_keep.erase("scratch");
+
+    if (!partitions_to_keep.empty()) {
+        std::unique_ptr<MetadataBuilder> builder = MetadataBuilder::New(*new_metadata.get());
+        if (!builder->ImportPartitions(*old_metadata.get(), partitions_to_keep)) {
+            return device->WriteFail(
+                    "Old partitions are not compatible with the new super layout; wipe needed");
+        }
+
+        new_metadata = builder->Export();
+        if (!new_metadata) {
+            return device->WriteFail("Unable to build new partition table; wipe needed");
+        }
+    }
+
     // Write the new table to every metadata slot.
     bool ok = true;
     for (size_t i = 0; i < new_metadata->geometry.metadata_slot_count; i++) {
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 3c6b1b7..e358bec 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -1200,6 +1200,15 @@
 void FlashAllTool::Flash() {
     DumpInfo();
     CheckRequirements();
+
+    // Change the slot first, so we boot into the correct recovery image when
+    // using fastbootd.
+    if (slot_override_ == "all") {
+        set_active("a");
+    } else {
+        set_active(slot_override_);
+    }
+
     DetermineSecondarySlot();
     CollectImages();
 
@@ -1223,12 +1232,6 @@
 
     // Flash OS images, resizing logical partitions as needed.
     FlashImages(os_images_);
-
-    if (slot_override_ == "all") {
-        set_active("a");
-    } else {
-        set_active(slot_override_);
-    }
 }
 
 void FlashAllTool::CheckRequirements() {
@@ -1243,7 +1246,7 @@
     if (skip_secondary_) {
         return;
     }
-    if (slot_override_ != "") {
+    if (slot_override_ != "" && slot_override_ != "all") {
         secondary_slot_ = get_other_slot(slot_override_);
     } else {
         secondary_slot_ = get_other_slot();