studyn

The higher pass mark is almost certainly due to the fact that more candidates spent more time studying (i.e. were out of work).

Given CFAI's MPS calculation (Modified Angoff method) it is very unlikely that the three-part answer would make the slightest difference. Suppose that all four answers had looked equally plausible. The MPS previously would have meant that 1 in 4 guesses were right; now it is 1 in 3, an increase of just 1 in 12. Given that you need around 2/3 correct answers to pass, this difference is just a few marks, a minor tweak in the MPS.

So each of you has a particular hurdle to achieve in order to pass, but that is entirely independent of how your peers perform.