Hey all,
I've booked a ticket ATL-JFK-LHR (Delta connecting to Virgin Atlantic) and return LHR-JFK-ATL. As my final destination is actually Paris, I'll need a way to get there from LHR. Right now, my options seem to be:

1) British Airways
2) Air France
3) Cross town to Victoria station, then Eurostar

I'm on the last flight out of JFK the evening of 5/25, arriving into LHR at 10:50am on 5/26. My return flight leaves LHR at 9:30am on 6/27.

Questions:

If I do end up flying, can my bags be checked through all the way to Paris (or, returning, JFK), or do I have to clear customs and/or passport control in LHR and then recheck? (I know the UK isn't in Schengen, but the Heathrow website seems to imply that connecting passengers have to clear some form of passport control.)

Also, June 27th is a Sunday. The earliest Eurostar arrives around 8:30a, leaving me zero hope of making it to LHR for a 9:30 departure. Thus, if I took the Eurostar, I'd likely take the train in the day before and spend the night in London. The first CDG-LHR flight on the 27th is a BA which arrives at 8:00a. Is this enough time to make a connection, and could the bags be checked through? (BA and Virgin are arch-rivals, as I understand it...)

Thanks in advance,

C.