Thanks Everyone -
When I looked on AA.Com guidlines I didn't see that the lounge used also had to be in the same terminal as departing from. It only mentioned that a departure was required the same day on a OW carrier. Admirals Club phone number also did not mention this whe I called.
FT Site & Members Help Once Again - Thanks.
Thinking about it more I may still try a trip into the city on the Paddington Express. It will all depend on how the airport looks.
- Craig