I was hoping to get some advice on what to do during my layover in LHR. We are flying BA First Class from SEA-LHR-SIN-SYD. We arrive in LHR at 12:00 and depart for SIN at 21:15, so we have about 9 hours. I do not want to go into LHR since we are doing a layover on our return. As a first class passenger, what facilities can I use? I hear there are cabanas that have beds and showers that can be reserved, but I don't know how? Is the arrival lounge close at 200pm? Can I pre-reserve spa treatments at Elemis? Any suggestions would be GREATLY appreciated!! Thanks