Sorry....thought "SCHEDULED relist" was meant in the past tense and you were actually seeing a missing gallery image.
Hmmmm....that is odd. I did 3 relists thought Auctiva on Monday night, and all 3 header-gallery images were fine. ebay is now forcing those to both be the same image (recent change), so there are a few folks reporting problems on relists with that kind of conflict. I did see Auctiva mention the problem, and they are changing the one-page lister to no longer have that option (next release). That's the only "problem" I can suggest as cause.
Only suggestions I can make for unknown cause are:
1. Ask Auctiva Support to take a look.
2. Wait for the relist to complete and see if the header and gallery image actually are there. If missing, just load the image on ebay's Revise listing editor.
Danno