That may be because you have one boxes referring to local posts. I made a topic about it but can’t quite remember the details.
If it’s just 2,you might just ignore it, but in rails you can find all the uploads that don’t have your new bucket in them. I think it’ll be empty?
I think the issue is that you have two posts that have some unexpected path in the cooked post.
I found it!
Can’t restore a backup if it includes link to Discourse onebox
Edit: so I think you’ve got two posts with local one boxes. I think you just need to find and rebake those posts.