I took this from the CMPB website.
"If you are medically graded PES A or B1, you will enjoy an 8-week reduction in your full-time NS duration if you attain 61 points or more from the three Pre-Enlistee IPPT stations (with a minimum of 1 point from each station) at least two weeks before the Physical Training Phase (PTP) enlistment in order to qualify for direct basic training. Otherwise, you are required to undergo the 8-week PTP."
61 points is a pass for active servicemen, which would mean as long as you pass, you should get the 2 months deferment.
However, personally, I was from the PTP batch, and I rather enjoyed it. I've had friends from PTP, and they say that their trainings are quite relaxed, as they have an extra 8 weeks, and it doesn't feel rushed. Kind of depends what company you are in, but my friend ha said that his trainings generally all end by 6, afterwards it is just admin time.
Of course, it there are things like outfield, or similar, that would not happen....