The issue has been resolved. Some tracks without art work in the metadata were being kicked out of the library, but there were no errors given to the broadcaster when this happened. This was not intentional and has been disabled. All upload capabilities appear to be restored at this time.
Some broadcasters were reporting that their uploaded files did not appear in the library. No error messages were displayed, and it looked like the upload was successful. We've tried to upload tracks on our end and some seem to show up as expected. We are continuing to investigate and the developers will keep us updated.