Just adding onto this as another with a similar/same issue. I read through a few pages of complainants, however I didn’t see anyone so far having the same particular problem - connecting to a local router/network which is NOT connected to the internet (intentionally)... it disconnects after about 30 seconds, even while I’m navigating local pages!! I can understand that Apple may have decided that, if a given WiFi connection is having intermittent INTERNET connection issues or speeds are drastically slow, it would revert to a cellular connection (for iPhone or tablets with cellular). That may be the case for some here, however, I would think that think that, developers of all people, would include a way to force WiFi (or Bluetooth), regardless of an external WAN connection or decreased speeds, etc...perhaps we just haven’t found the solution yet? Doesn’t seem that way thus far...WiFi Assist does not do the trick. It may stay connected a few seconds longer, but ultimately disconnects from WiFi. The only way I can stay connected is if I turn off cellular completely (I’d still like to receive a phone call though...)... On a side note, iOS 14.3 was crashing a bunch of apps initially. I haven’t payed attention as to whether the ones that were crashing were updated and I haven’t seen any crash in the past day or two (as of 1/20), but something is definitely going on with 14.3...perhaps some more political nonsense, like slipping in COVID vaccination tracking?? I feel bad for others who are having a more critical need for a resolution, and hopefully adding to this list will aid in that. I usually don’t post about these kinds of issues but Apple definitely needs to have a more swift response... iPhone 8 Plus iOS 14.3