Travelling F in 28 days time on a Monday, emailed through the web form, no slots available
This is pretty poor, the spas clearly need more slots if even those who are meant to be able to pre-book are unable to get a slot (on a Monday) without calling 2 mins after availability opens
Luckily my girlfriend and I are planning to go to LHR about 4hrs before the flight so we can enjoy the lounges, do a bit of shopping and generally have a relaxed "set off"...from what I am reading 4hrs early should be enough to get a slot on the day