Hey ND, you are one brave cook to take on that assignment, particularly if you haven’t done it previously. I hope you have a few extra pairs of hands to help.
You are serving a commercial-sized group and your APC with its 900 watt output and about 2 gph flow is designed for home use and its associated thermal loads. Please cook in smaller batches in an insulated vessel. For successful SV cooking you need ample water circulation.
If you are considering using bone-in loins, - don’t. Why? There’s the excess mass, they often need to be double bagged because of the bones, plus all those bones to mess with that will woefully slow your portioning and service.
I’d use boneless back halves, or even better, only rib-half boneless loins which are relatively uniform in shape end-to-end and shorter with less end-trim to ease portioning and service. I have always used 2 1/2 portions per pound as my edible portion guide in catering while rounding up. It’s lots, unless you are serving a couple of football teams and offering “seconds”.
If at all possible, you will achieve a superior product by adding tenderness and moisture if you brine the pork before SV bagging with a 4% sea salt and 2% brown sugar solution for 12 to 24 hours. Besides, it adds flavour too.
Since you have a commercial kitchen available you have the option of straight oven roasting low and slow on the day of service. (i know, - outrageous heresy here, but it works particularly if you want medium done pork for 100. Serving medium done pork loin is beyond my comprehension, but i know it happens.
Alternatively, i’d suggest considering a SV cook at 140F, no higher, for 3 to 6 hours. That will result in tender, pink - not red, moist roasts. Anything over 150F is going to toughen that lean meat and render your SV cook efforts almost useless. Although it will result in producing lots of juices for your sauce. Give yourself ample time to wrestle with those pork loins on the griddle, and it’s going to be a beast to clean. Get some 18" tongs too.
Be sure to save the fluids in the bags for your Onion and Herb Pan Sauce.
You are going to make gravy, aren’t you? Put it over the meat for your medium doneness guests and under the meat for those that enjoy perfectly cooked pork.