Brew Schedule flexibility

I put together a yeast starter last night for a Belgian Strong Ale. The yeast had an expiration date on it of 11/30/06. While it is almost a year old, I'm going to try and harvest what is left, and try to step up a nice starter for an upcoming batch of beer. Ideally I would like to brew it this Thursday night, but given the potential high starting gravity of this beer (>1.080). I may need to rethink my plans.
Between the year old yeast and the high gravity of this beer, there will be limited margin for error in regards to pitching enough healthy viable yeast to start fermentation.
With that said, I may end up brewing the house pale ale Thursday night and save the Belgian strong ale for sometime next week. The fermenters will finally be at maximum capacity.
A kind word of thanks to those of you who have offered me solutions on my carboy dilemma.
May beer karma be with you.