Same law also says that Michigan electors meet at 2 PM ET. Not sure how C-Span has it scheduled for 3 hours earlier.
I don't see any restrictions on PA electors voting choice. But PA law says they are supposed to meet at Noon. Again, not sure why C-Span comes on and hour earlier?
Maybe they have a long pre-game show with lots of analysis and strategy from former electors and coaches from the Electoral College.