I have an iPad 6th Gen LTE running iPadOS 14.7.1 that is stuck on 0% downloading 15.1:

Looking at the Troubleshooting log, I can see the download taking place, but not getting past 0% (this is repeated over the past couple of days):

The user has tried restarting their iPad but this hasn't helped. The iPad is plugged into a wall socket (battery level at 100%), connected to stable Wi-Fi and has plenty of available free space (12 GB). 

I came across https://support.apple.com/en-gb/HT201435 which says you can delete an update by going into Settings -> General -> [Device name] Storage and tapping "Delete Update". I'm going to try this next, with the user when they come to see me. 

Has anybody experienced anything similar in the past?