diff --git a/payload_consumer/partition_update_generator_android.cc b/payload_consumer/partition_update_generator_android.cc
index 25771e1..4467182 100644
--- a/payload_consumer/partition_update_generator_android.cc
+++ b/payload_consumer/partition_update_generator_android.cc
@@ -41,6 +41,11 @@
         BootControlInterface::Slot target_slot,
         const std::set<std::string>& partitions_in_payload,
         std::vector<PartitionUpdate>* update_list) {
+#ifndef __ANDROID__
+  // Skip copying partitions for host verification.
+  return true;
+#endif
+
   auto ab_partitions = GetAbPartitionsOnDevice();
   if (ab_partitions.empty()) {
     LOG(ERROR) << "Failed to load static a/b partitions";
diff --git a/payload_generator/generate_delta_main.cc b/payload_generator/generate_delta_main.cc
index 2e32f1b..8cda9d1 100644
--- a/payload_generator/generate_delta_main.cc
+++ b/payload_generator/generate_delta_main.cc
@@ -183,8 +183,11 @@
   install_plan.source_slot =
       config.is_delta ? 0 : BootControlInterface::kInvalidSlot;
   install_plan.target_slot = 1;
-  payload.type =
-      config.is_delta ? InstallPayloadType::kDelta : InstallPayloadType::kFull;
+  // For partial updates, we always write kDelta to the payload. Make it
+  // consistent for host simulation.
+  payload.type = config.is_delta || config.is_partial_update
+                     ? InstallPayloadType::kDelta
+                     : InstallPayloadType::kFull;
   payload.size = utils::FileSize(payload_file);
   // TODO(senj): This hash is only correct for unsigned payload, need to support
   // signed payload using PayloadSigner.
@@ -576,6 +579,10 @@
     }
   }
 
+  if (FLAGS_is_partial_update) {
+    payload_config.is_partial_update = true;
+  }
+
   if (!FLAGS_in_file.empty()) {
     return ApplyPayload(FLAGS_in_file, payload_config) ? 0 : 1;
   }
@@ -604,10 +611,6 @@
     CHECK(payload_config.target.ValidateDynamicPartitionMetadata());
   }
 
-  if (FLAGS_is_partial_update) {
-    payload_config.is_partial_update = true;
-  }
-
   CHECK(!FLAGS_out_file.empty());
 
   payload_config.rootfs_partition_size = FLAGS_rootfs_partition_size;