No idea. I'd just guess that it's the "too many things happening at once" scenario. As it's currently bank error in your favor, I'd not worry about it. Just watch it and see what happens. As long as it comes out no worse than even, it's cool. If additional last-minute fees get added, just call and make sure that those get removed.

You know how it should work out, and how it has. Just chill until something needs to be done

Cheers.