diff --git a/build/mainline_modules_sdks.py b/build/mainline_modules_sdks.py
index aef518f..4de99ec 100755
--- a/build/mainline_modules_sdks.py
+++ b/build/mainline_modules_sdks.py
@@ -728,7 +728,7 @@ R = BuildRelease(
 )
 S = BuildRelease(
     name="S",
-    # Generate a snapshot for S using Soong.
+    # Generate a snapshot for this build release using Soong.
     creator=create_sdk_snapshots_in_soong,
     # This requires the SoongConfigBoilerplateInserter transformation to be
     # applied.
@@ -736,9 +736,16 @@ S = BuildRelease(
 )
 Tiramisu = BuildRelease(
     name="Tiramisu",
-    # Generate a snapshot for Tiramisu using Soong.
+    # Generate a snapshot for this build release using Soong.
     creator=create_sdk_snapshots_in_soong,
-    # This supports the use_source_config_var property.
+    # This build release supports the use_source_config_var property.
+    preferHandling=PreferHandling.USE_SOURCE_CONFIG_VAR_PROPERTY,
+)
+UpsideDownCake = BuildRelease(
+    name="UpsideDownCake",
+    # Generate a snapshot for this build release using Soong.
+    creator=create_sdk_snapshots_in_soong,
+    # This build release supports the use_source_config_var property.
     preferHandling=PreferHandling.USE_SOURCE_CONFIG_VAR_PROPERTY,
 )