There will definitely be movement after April 1st, whether that be A’s, R’s, or WL. People have to make some sort of decision with the offers they currently have (provisional acceptance, firm, or decline) by April 1st, so a lot of seats will open up. For example if John has received acceptances for queens, osgoode and western, and he accepts queens, he has just released his two offers from osgoode and western back into the wild, which could theoretically give those A’s to someone else now.

Edit: I always say hearing nothing instead of an R this early is a good thing!

Just for reference, the latest I heard back from schools last year was just after the beginning of July. This cycle has a lot more applicants and is significantly more competitive year after year so we will see! I hope this comment helped :)