I’ve been a happy OSMC/RPi2 user for some time now, thanks!
I just upgraded to the Kodi 15.2 release and was surprised to discover that I had no wi-fi connectivity after reboot. I don’t have a keyboard for the Pi, so I hooked up ethernet and was able to then get to the UI with my remote. Then, I went through the wi-fi connection dialog and was able to reconnect.
No idea why that happened, but FYI in case someone else runs into this.
New kernel etc simple reconnect will fix this nothing major its the same when you install new driver on windows 
True, except that this isn’t Windows, so we hold it to a much higher standard. 
It’s not going to be kernel related.
If the network was saved then it should still automatically reconnect after the update. More likely the wireless connection just failed to connect for some reason but you didn’t wait long enough (several minutes) for it to automatically try to reconnect, manually reconnecting hurries this process along.