Probably not, it always says it'll take a good 30 days before the subscription starts. If they mean the May issue incidentally that'll be with you at the beginning of April, so a month from now (more or less).
Yes, the May 2012 issue goes on sale April 5th, with subscribers getting theirs (post allowing) on April 1st/2nd. It does normally take a month for new subs orders to work their way through the system.