Sounds like you got a refurbished piece of garbage. You should have declined it when they first gave it to you. I know it's a huge pain, but you do have that right. Can you get to Recovery and clear the cache partition?
I would not take a refurbished phone for their update killing my phone... There is just no way. I'd be calling the BBB if they didn't want to work with me.. That's just ridiculous.
Sent from my T-Mobile HTC One using AC Forums.