No, the yeast should be just fine. Depending on the additives, I'd add 3 times the acid to balance it (however, taste should decide when almost finished), and I'd break up the nutrient in 3 phases, before ferm, 2nd day of ferm, and 4th day of fermentation! Breaking up the additions of nutrient makes for an earlier drinking wine. I'm not sure why, and I've yet to come up with a scientific reason. But by all reports, it works!
edit: So in other words: Triple the recipe, except for yeast.Edited by: Dean