Your focus seems to be on 12-13 July.
As mentioned above, this will not be a long week-end this year. When a long week end, it is extremely busy because school holiday typically start a few days before and working parents take advantage of it to fly their kids.
The best indication for you is to look at the loads on PVG-CDG-YUL.
EF indicates that the flights still sell fairly cheap fare buckets.