I have the same issue on 2 86U routers. This started with 384.17 I think, maybe .16, cant remember exactly. I use the WebUI less than once a week, maybe 2 to 3 times a month but for a while I was using it 2 to 3 times a week... and it seems like once every week or so I'd need to physically reboot a router to get to the UI. And this is still the case now as the reason I looked for this thread was I just rebooted my main router.
This is 100% definitely a bug/problem with the firmware as it didnt happen in .15 or maybe .16
This is 100% definitely a bug/problem with the firmware as it didnt happen in .15 or maybe .16