Planescape box set art not loading

The art for the three Planescape books appears to have stopped loading in properly. I checked on a couple of different devices, and checked other books as well, and it seems to be confined to just this set of books--though I haven't done an exhaustive check. (These happen to be the ones I'm running right now.)

I'm also having this problem. Switched browsers as well but to no avail.

This is happening to me as well. Requests for pretty much all the images outside of monster stat blocks are returning 403.