Because CIC hasn't done a first-Friday-of-the-month draw except in Feb and Aug. Feb 7th was an accidental draw which pulled out the exact same number of candidates as Jan 31st draw while Aug 7th happened because July had 2 back-to-back draws leaving the last 2 weekends in July with no draws so the pool had enough replenishment time by Aug 7th.
The most recent draw happened on the penultimate Friday of August and counting for 2 Friday gap till next draw leads one to conclude that CIC is likely to draw on 11th Sep (or later) but not earlier than that. Which might not be a bad thing because if they do 2 draws in September the 2nd draw will happen on 25th (with a gap of 2 weeks) and that will push the cutoff to 450 or even slightly lower than that.
It is of course possible that CIC does 0 draws till January 2016 or does 1 draw/month or just keeps the cutoff artificially inflated till it suits them because they have already achieved the lower limit (15) of their anticipated draw numbers for 2015.
Not trying to scare anyone but these are the facts - I'm waiting for an ITA myself and my score (450+) has taken a beating from the last time around.