that decision is from Ontario and not CIC...moreover it is driven by the below logic
1.if they keep nominating only those above 400,they might not get the desirable mix of immigrants
2.With cut off coming closer to 400,and with a window of 6 months to respond,those who gets NOI decides to wait...and that puts their numbers in uncertainty & they might miss the whole year target...if they issue NOI to those who are hovering in 300+ those are sure to snatch the opportunity...so an NOI issued will become an application quite fast.
if their idea was to influence the cut off,why couldn't they simply issue nominations to those with 400+..there are sufficient numbers to meet their yearly deficit of less than 3000
anyway, the PNP is not counted in the economic class....CIC will have to discount the total PNP ITAs and issue additional to complete their budgeted numbers...