Upgraded to FIOS TV One, and they "automatically" upgraded me to Premium DVR service with 2 media servers, which I did not want, nor ask for.
I've spent hours on the phone with Verizon trying to get this resolved, talking to so many people. Everytime they put in an "order" to downgrade back to the Advanced service, it never ends up going through and disappears into Neverland.
I remember reading on the forums about some people trying to upgrade to FIOS TV One online, and it made them select Premium DVR service when they did. I think this must be related, because I upgraded to Fios One over the phone, and there was never any mention of upgrading from Advanced to Premium at that time, and no one seems to be able to downgrade the service. I've been transferred to a ton of different departments and have spent hours on the phone with Verizon trying to get this simple request done, but it seems impossible.
How many stbs total do you have? If you happen to have more than 5, then you have to have 2 VMS. 5 or less, you should be able to downgrade.