I have a 4 keg setup and am about to empty all 4. I just found out that I only have 3 beers in fermenters ready to go: imperial stout, IPA, & Hefe. I like to fill all 4 kegs at once. What is a beer or style that I can brew and have in the keg in a short period of time? The only yeast that I have on hand is Danstar British which I would prefer to use.