Not completely true, my bf is an April applicant and he got his MR January 14th, he got reminder email at the same time. So I think some June applicants could expect to have to still wait a while for MR.
It seems like CIC has been changing around the order the they do things (likely to see what is more efficient) So, I wouldn't look to much at the oder and timing past applications got requests in. It does seem like MR is coming near the end of the process rather than the beginning. This saves people having to redo medical if the application is delayed more than a year. It does seem like the current total processing time is a year (at least for inland applications). I have a feeling this time will decrease as they seem to be catching up on backlogged applications. I have a feeling that June can expect MR end of February or even Aas late as early March but I think it will be fast after MR and that most June applications will be done and have COPR by end of April or beginning of May.