[DannyBee]

As mentioned, i suspect the argument they will try (and what Jeff Sessions appears to have said) is that congress intentionally chose not to regulate this space when they promulgated the comprehensive '96 act and didn't say anything.

Then it doesn't matter what the FCC does.

This is a bit weird of an argument because congressional intent was so unclear that the FCC tried to regulate it many times :) (and it required a court deciding what the statute said).

The FCC can reinterpret its own statutes, actually, including ones that say how much authority it has. Those interpretations are subject to various standards around precedent and consistency. I doubt they would meet them here if they suddenly reinterpreted them.

(Note also that appeals courts are becoming more concerned about the deference given here to agencies to say what their statutes/regulations mean, and the supreme court is likely to take it up again sooner rather than later)