I suppose, but that particular plane has flown at least 1 long haul leg nearly every day the past 2 weeks----lots of back and forth JFK/Atlanta/west coast to Heathrow, even Lagos Nigeria. I can't believe they are all ferrying pro sports teams or groups late enough to need 100+ 1st class seats. Reconfiguring the plane for 100% lay flat 1sts would take easily a day or more and could only be done at an airport where Virgin had such equipment stored.
The turnarounds one these flights suggests that's impossible.