SERVER-45047 made the setFCV command block chunk migrations by locking the ActiveMigrationsRegistry. This forces the setFCV command to wait for any ongoing migrations to complete. SERVER-45624 made the balancer automatically split the config.system.sessions collection so when the setFCV command is run after the balancer is re-enabled, there is the chance that the setFCV command is blocked behind a migration for the sessions collection. Since the range deleter waits for orphanCleanupDelaySecs before checking if the collection exists and doing the deletion, the range deleter is forced to wait orphanCleanupDelaySecs (defaults to 15 minutes) before failing with RangeDeletionAbandonedBecauseCollectionWithUUIDDoesNotExist which is then ignored. To solve this, we should check if the collection exists before submitting a range deletion task here when we call _notePending().