I have problems with the wifi on a different phone, a Pro5, since I purchased it and never understood why but I always thought this phone wasn't a lucky one.
I'm on 16.04 Devel but it doesn't work regardless of the channel, and on the Vivid image as well.
The wifi is working when I reinstate the credentials every time, but it doesn't automatically show up at every reboot, as the Access Point credentials didn't exist before. I read @Flohack reporting about a MAC number problem, so I tried to investigate to see what happens on the phone at reboot.
After rebooting, I checked the var/log/syslog and I found a MAC verify failed kernel error. @Osndok, by the chance do you have the same error? Could it be related to the fact that the wifi doesn't work?
If of any interest, I provide part of the syslog HERE.
Matteo