How did you solve this by the way ?

Hi - I'm facing the same issue. I uploaded the app previews and it's been over a few hours and they say "uploaded and processing." I'm not able to submit the changes for review until this is done. I have tried to delete and re-upload several times. What do you recommend I do? I've responded several times. Also when I go through other tasks etc when I come back there is a red exclamation mark in a red circle. I've reuploaded again I then get the cloud icon. If I Try to submit its the same processing message then a red exclamation mark. Very frustrating as the exact same previous video worked on a previous submission ! So it's not the video