Most KE A330s (other than ones used for intra-Asia short-haul) will be Prestige Sleeper, while 747s are all Prestige Plus (angled lie flat). 777s come in two flavors: Prestige Sleeper and Prestige Plus. So, this may very well be an upgrade: instead of Prestige Plus angled lie flat on 777 (as it very well could have been before - unless you checked the seat map and configured it was the PS config?) now you'll get the true lie flat PS on the A330.