My guess is the EWR-SFO-EWR three-cabin 777 flight goes to a 77W once the last A-market 772 leaves the US for conversion to 77G. Both EWR and SFO will be 77W 'bases' and so operating the early 77W flights between those stations makes sense.

I suppose EWR-ORD-EWR could end up being a 77W flight too during the January timeframe, but the 4h ground time at ORD seems less than efficient to operate the flight as a turn. I wouldn't be surprised if the flight will be used to rotate 777-222ERs throughout the EWR and ORD longhaul networks, as the seatmap currently shows the ER configuration (29/30DEG as standard E+ seats). EWR-FRA, in particular, remains a 3-cabin 777 through the current schedule, so this flight could be part of an aircraft rotation.