According to another site, there are 2 different bus routes:
Bus A leaves every 15 minutes going to the TTC, to catch monorails to Epcot and MK.
Bus B leaves every 30 minutes, stops at AK, then Blizzard Beach, then MGM. It is about 45 minutes to MGM according to the site.
For our trip in Sept, I think we'll walk to Poly to get the monorail to MK, take the bus to TTC to get the monorail to Epcot, take Bus B to AK, and drive our own car to MGM.
Claire