diff --git a/lib/model/query/forms.js b/lib/model/query/forms.js
index be489ad0c..17522ac1c 100644
--- a/lib/model/query/forms.js
+++ b/lib/model/query/forms.js
@@ -486,7 +486,7 @@ const _draftFilter = (form, project) =>
       : sql``));
 
 // NOTE: copypasta alert! Similar SQL also appears in 20220209-01-purge-unneeded-drafts.js
-// Purges draft form defs that are not referenced by any forms AND have no associated submission defs.
+// Purges draft form defs that are not referenced by the form as either currentDefId or draftDefId AND have no associated submission defs.
 const clearUnneededDrafts = (form = null, project = null) => ({ run }) =>
   run(sql`
 DELETE FROM form_defs