pwc assessment day

I had an AC with EY, although not PWC, I would assume it is a similar process. I was contacted the following day with a successful invite to the final round - partner interview whilst my friend was rejected just a few hours after. I would assume they go through and spot the straight up successful candidates and rejections, and reply within the first couple days, and after that the more "maybe" candidates who they need additional time to decide. So it is possible you fell under that "maybe" group and they are still considering you. I would just wait until the 14th and if you still have no reply, politely email them.

Also it is possible they have had an other AC recently or have another in the future and are waiting to finish all of them before making any decisions.

F.Y.I. I could be wrong, I am just making assumptions. Good luck!