>>273813543
No, I'm not into that sort of thing to be honest with you. 
Thankfully I have no solved it, I think. 
I had to actually re-pair it to my phone, despite it already being paired, and go through the entire initial setup process again, which itself was a pain because the process was hanging at every step until I held the power button to turn off the quest, then turn it on again. Repeat that for every step until finally it all just went "ding" and it's working fine. 
My account is back on my Quest, all my applications and friends are still there and it's like nothing ever happened. 

I wonder what it was?