This does sound like a driver problem, so I think you are on the right track with that. If everything was working in 15.10, then the drivers are out there that should work. Unfortunately, there is a lot of leg work involved with finding out which driver(especially when it's an older driver and there is no record of it). I have noticed that Ubuntu MATE took a few reboots to get my graphics drivers sorted out after I updated today, so hopefully, if you sudo apt-get update then sudo apt-get upgrade, and reboot a few times, it will start 'magically' working again.
It took 5 reboots and some messing with the Nvidia driver software to get things sorted out for me.
I know graphics and printers are completely different beasts, but hopefully you will have just as easy a time getting your drivers going again.
Check in the System menu, Preferences, in the Hardware and check to see if the proprietary driver for your printer is there and has been turned off(or unchecked). That's what happened when I updated. The system will sometimes reboot to its default drivers, and you will need to turn them back on and reboot again and maybe again.
Hope this was useful, even just so you know people are reading these.