This was indeed an intentional change. Concurrent uploads within a single account were causing corrupt documents. We are unable to provide that functionality because of the inherent risk to content.
I think the suggestion for UI to provide multiple article selection/action is a fine one. I'll file it and take credit for it myself (just kidding). It would certainly be worth considering.
Not sure how my suggestion wouldn't cause the problem you discovered. Personally I have had a lot of object states drop off recently and the only solution was to rebuild the file but with some articles having 15+ pages and one evern 80+ it's not practical.
Personally I would love there to be an 'update folio' option so that when you have had to change every single article you can just set and forget. If you only change 3-4 then a multi-update selection would be helpful too though.
But thanks for the quick response.