Yahoo never recognizes the day the trade was actually accepted. They start counting at the first midnight after the trade was accepted. If the trade was accepted on Thursday, Yahoo will recognize Friday & Saturday as your 2 day waiting period. Sunday at 12 am is when your trade becomes official.
That is why, as commish of my league, there is only a 1 day waiting period on trades and WW material. Because Yahoo is like a dog... a year to us is 7 to them.
8 Team Head-to-Head League:
QB: Tom Brady, Brett Favre
WR: Derrick Mason, Joe Horn, Santana Moss, Lavernues Coles
RB: Ahman Green, Fred Taylor, Brian Westbrook, Reuben Droughns
TE: Tony Gonzalez
K: Jason Elam
DEF: New England, Seattle