Won't be that, we haven't used backup data for a very long time.
The problem is with the listings being marked as "deleted" from Auctions I Ran, our database is saying it has been marked as deleted so we don't show it to the user but the user reports never having clicked the "delete" checkbox in Auctions I'm Running.
We've installed date stamps so we can track down to the second when an item is deleted from Auctions I'm Running in the future, just give us your auction IDs when you have them and we can look deeper into this.