everything Lougle said about her cold start yogurt is correct, but technically you are supposed to boil the milk first so that any random and possibly harmful bacteria doesn't get the chance to make poisoned yogurt. It's only the good yogurt bacteria from the added starter that is there to grow
That's why you don't have to boil UHT (or the cravendale I suppose) as the possible bad germs are already dealt with.
TBH if I wasn't a bit prissy about dairy stuff I wouldn't bother either with the pre steam/boil. Happy to totally ignore sell by/use by dates on no end of things including yog/milk/cream but somehow making my own makes me all germ conscious 
Today I am making a cheesecake! ...it's baking day so there will be a banana loaf too, and maybe cheese scones and soup.
Cru Cru ...I'd press the stew button and let it get on with it , if it's cubed you are heading down that route, rather than a roast anyway. Or maybe you could cook the pork...onion, celery, tomatoes, paprika, add a handful of rice, go a bit Polish/Austrian with your seasoning, and then blanch your cabbage leaves and stuff them with the pork mix, thicken any left over sauce pour it over and finish the lot in the oven.