Android 11 is requiring me to connect to WiFi to do a system update, and I have found no way to use mobile data to do that. The problem is, what if I do not have access to WiFi data? In the past, my smartphone stopped connecting to the Visible network until after I did a system update. If that happens again, and I do not have WiFi access, I'm screwed. Is there any way I can update the system using mobile data?
While obviously not the best solution, have you tried attempting to connect to WiFi service when out and about that may be available from a shopping center/coffee shop etc.? Depending on how often the update needs to connect to WiFi that may be an option.
Secondly, not sure if it would work but does connecting to a mobile hotspot trick the system thinking it is on WiFi.
Finally, check your settings in your phone to see if there is a data saver option checked. Possible because the update is to large it is trying to save cell data and force it over WiFi.
I am not familiar with Android phones/apps so I apologize if my suggestions are not helpful, but trying to at least get you some sort of assistance.