In early August, irrespective of your experience or fitness level, I'd plan for no more than one major pass per day. It's definitely possible to do it faster, but that's dependent on the weather. You have to be prepared for the possibility that thunderstorms may utterly shut you down by 11am daily, if you've got a pass to cross and lightning is striking all around you.
Conveniently, major passes are all about a dozen miles apart on the UHT, so it's relatively easy to plan 12ish mile days, camping right before the pass so you can go over it first thing in the morning while the weather is at its most stable. Anything more than that is rolling the dice, in my opinion. Can you get away with it? Maybe, but rushing it greatly decreases your chances of success.