This is absolutely a backend sync bug that rolled out with Meta's October 28-30 release cycle, and you're not alone - we're tracking this across multiple accounts. The "Include other products from your catalog" toggle is reverting to checked state after successful publish, typically within 2-6 hours. It's not a cache issue or team edits - it's server-side state management failing between the UI layer and the actual campaign delivery settings. What's technically happening: Meta's Catalog Sales campaign settings use a two-tier storage system. When you uncheck that box and publish, the UI writes to one database while the delivery engine reads from another. There's normally an instant sync, but something in the recent rollout broke that handshake. The delivery system falls back to default settings (which include showing similar products) when it can't confirm your specific exclusion preference. Your ads are actually serving the wrong products because the backend genuinely thinks you want catalog expansion enabled. Critical workaround until Meta patches: Switch your campaigns from "Catalog Sales" objective to "Sales" objective with manual product selection through dynamic ads. Use product sets as normal, but specify product IDs directly in the ad creative level rather than relying on the campaign-level toggle. This bypasses the buggy setting entirely. For existing campaigns, duplicate them with this structure instead of trying to fix in place - editing existing campaigns triggers the bug repeatedly. Document every instance with screenshots showing the setting unchecked vs auto-checked, include UTC timestamps, and reference your case ID in any Meta groups you're part of. The more documented instances with case IDs, the faster engineering prioritizes the fix.