FAILURE MODE: Offer schema with a long-expired priceValidUntil

FAILURE MODE: Offer schema with a long-expired priceValidUntil
Sites add Offer structured data once and forget it. Months later your JSON-LD still claims the deal is valid through a date in the past, or worse, hardcodes a discount that's long gone. Google quietly drops the rich result and may flag the structured data as misleading.
The fix: Make priceValidUntil dynamic — tie it to the actual code expiry in your database, not a static string. When a code dies, the schema dies with it the same hour. Validate the merchant hub in the Rich Results test after every offer rotation.
Why it matters: Bad schema doesn't just fail to help — repeated mismatch between your markup and your visible page is a manual-action risk. Wrong markup is worse than no markup.