Currently you can't buy a first class seat on a 3 class 752PS. you can buy Y+ & J. They sell all the flatbed and lounger seats as business to avoid problems when the planes are finished being converted or if a converted plane is substituted in for an expected 3 class. To decide who gets the flatbeds elites are given access to selecting them first and the airline assigns them to elites over purchase category. I've watched it done and got stuck in the lounger as I am statusless this year