Moving within the same apartment and I have to have fiber-optics?

The question is pretty much straight forward as possible. I was on the phone with an AT&T representative and I just wanted to move my service, Basic DSL Service, to a new apartment number, which is in the same complex. The representative said due to the fiber-optics, I have to buy a new modem. I thought fiber-optics is just an upgrade you can choose? I have not spoke with the administration of the apartment about this just yet but I will. Can anyone help clarify this in the meantime? I tried to call back and find out more info but of course, I was on hold with AT&T for 2 hours and was not able to get through. Thanks