diff --git a/src/wormhole/server/db-schemas/upgrade-to-v3.sql b/src/wormhole/server/db-schemas/upgrade-to-v3.sql
index b613f8f..69bb255 100644
--- a/src/wormhole/server/db-schemas/upgrade-to-v3.sql
+++ b/src/wormhole/server/db-schemas/upgrade-to-v3.sql
@@ -60,6 +60,7 @@ CREATE TABLE `messages`
 );
 CREATE INDEX `messages_idx` ON `messages` (`app_id`, `mailbox_id`);
 
+ALTER TABLE `mailbox_usage` ADD COLUMN `for_nameplate` BOOLEAN;
 CREATE INDEX `mailbox_usage_result_idx` ON `mailbox_usage` (`result`);
 CREATE INDEX `transit_usage_result_idx` ON `transit_usage` (`result`);
 
diff --git a/src/wormhole/server/db-schemas/v3.sql b/src/wormhole/server/db-schemas/v3.sql
index 751d0ed..e447744 100644
--- a/src/wormhole/server/db-schemas/v3.sql
+++ b/src/wormhole/server/db-schemas/v3.sql
@@ -83,6 +83,7 @@ CREATE INDEX `nameplate_usage_idx` ON `nameplate_usage` (`app_id`, `started`);
 CREATE TABLE `mailbox_usage`
 (
  `app_id` VARCHAR,
+ `for_nameplate` BOOLEAN, -- allocated for a nameplate, not standalone
  `started` INTEGER, -- seconds since epoch, rounded to "blur time"
  `total_time` INTEGER, -- seconds from open to last close
  `waiting_time` INTEGER, -- seconds from start to 2nd side appearing, or None