Depending on when you're planning to visit, it's still not a bad idea to book at current rates and see what happens.
FWIW, last time we visited in February, I booked our room at HRH 9 months ahead of time. A few months later, just before releasing February "Passholder Discount" rates, Universal jacked up the price of all of the rooms at all of the onsite hotels for the week we were visiting (which was President's Day week, a popular holiday), some to double what they'd been before, such that we would have paid 30% MORE if we'd rebooked the same room at the passholder rate instead of keeping the full rate we'd booked ahead of time.
If they can trick you into paying more and thinking you're getting a deal, they will.