[Official Census docs (warehouse-managed audiences)]: Audience membership lives in your warehouse's audience membership table, and Census queries it just-in-time, so adding or removing rows updates membership on the next sync. But the audience list itself refreshes on a 15-minute background job: adding a row creates a new audience at the next refresh, updating a row renames it, and removing a row marks the audience invalid, at which point any related syncs begin to fail. You can manually delete the invalid audience or re-add the row. Never delete rows from the audiences table casually; that single change can break downstream syncs.

Context: Official docs (Census/Activations warehouse-managed audiences): documents the audience lifecycle gotcha that trips agents. Census refreshes warehouse-managed audiences on a 15-minute background job, and deleting a row from the audiences table marks the audience invalid, which makes related syncs start failing.