It's right in the CFL constitution.
http://media.cfldb.ca/documents/appe...nstitution.pdf
(b) Not later than September 1 in the calendar year preceding the schedule year each MemberClub shall inform the Commissioner which dates, if any, are not available for a game in its homestadium, and shall further advise which dates are most preferred for its home games.(c) The Commissioner shall prepare, or cause to be prepared not later than October 15, a draftschedule of games to be played by each Member Club and shall distribute a copy of the totalschedule to each Member Club for its comments.
I have no idea when MLS or VCup schedules are decided, or at least the drafts. If a Draft schedule is complete for the CFL 4 months before the actual release. I'd imagine it should be something similar for MLS as they have to fit in more games with more teams.
Oh, M, I wasn't doubting your authority on CFL scheduling I was referring to the scheds you don't follow (like myself, I don't know how early they need to decide either). With the little notice we get here following Vcup and friendlies it has to be a challenge adding another schedule to the mix.
FORMER FULL TIME KOOL-AID DRINKER