I'm getting Sonic installed at a new address, and I'm trying to wire the house prior to service installation. Sonic's availability tool says I'll be getting IPBB-C. Do I only need to run 1 pair of copper from AT&T's PoE to the room I want to put my modem?
Depends. If you plan on using two DSL circuits bonded, you would need two pairs.
Do you have an alarm system ? Is it wired with an RG31x (so alarm system has priority to call over other voice lines in the house)
Will you put dsl filters on splitters by phones or in the demarcation box? if so, you will need separate pairs for voice and data from there.
I believe the installer should be able to do it unless policies are different in covid time and they don't enter your house/basement?