Masters SSHRC/CGS results are sent automatically via email on April 1st (as with Vanier), whereas the Ph.D. results are sent by regular snail mail. They're different competitions with different adjudication and administrative processes and timelines.
According to some veteran Ph.D. students in my department and from my experience with colleagues at different universities across the country, the Ph.D. results have pretty consistently only been released at the end of the month of April. I suppose that if you live in Vancouver, up North, or in the U.S., etc., the letter will take longer to arrive from Ottawa as well. I'd say that it's safe to assume that we won't hear anything until the week of April 30th. Anything earlier will just be a welcome surprise :).