It’s not something I would recommend.
Already there have been some significant package changes to 11.3 thru the Milestone releases, I am talking about X config.
Even though I can easily work my way thru all the moves to ‘dup’ to a final, when it’s released I will still do a fresh install. Takes less than 20 mins and then maybe another hour to get everything else in place.
I currently use M7 and could ‘dup’ to RC, but I’ll be doing a fresh install to give the install a good testing. Of course I am involved in bug testing so I would do that.
Hope that makes sense.
Incidentally, is it the kernel that fixes your issues or a combination of things?