Since we're talking CO through baggage queries may as well pop mine here too and save a new thread.

Flying LHR-EWR-SDF on Friday.

Decided to go on the early LHR-EWR and the late EWR-SDF to give me 6 hours or so to head into NYC for a spot of Christmas shopping.

1) Will I be able to check my main bag onto the EWR-SDF immediately upon arrival in EWR (i.e. 9 hours before the flight).
2) If I do lots of shopping will I be able to check a second bag later on re-arrival at EWR?

Star gold so no need to worry about fees for first 2 bags.

Thanks in advance