ATT/GFiber and CGNat

I have ATT 1gb fiber at the moment but I was looking to upgrade to 2gb. I haven’t been paying attention and it turns out I can do that with either ATT or google fiber and it would cost $10 less than I am currently paying. My only concern is I don’t want to upgrade to find myself behind a CGNat and wanted to know if either of them implement it. Otherwise I’ve had no problems running my homelab off my current att fiber plan.

Also question to anyone with google fiber, are there any issues related to running a homelab that you’ve run into?