I've seen them on all room types. However, given that Universal is more likely to offer incentives [of any kind] during times of year when occupancy is lower, the timing of your visit is likely to impact the availability of AP rates, and the number of room types for which they're offered.
Anecdotally, I've found that when we visit during, say, President's Day week (which is a big holiday break for most schools in the northern U.S.), AP-discounted rooms are few and far between, and will mostly be limited to standard rooms, with limited dates (e.g., weekdays only). When we've visited during less busy times of year, when hotel occupancy is lower (e.g., end of August), there have been many more AP-discounted room types offered, even for suites and other "special" rooms, and for longer date spreads.
On a side note, if you're visiting during a holiday week, I'd caution against "waiting until AP rates are released" to decide whether (and where) to book. The last time we visited Universal during a February break, I booked HRH a year ahead of time, when no discounts were being offered (although Savvy Traveler and Stay More, Save More discounts can often be available that far ahead), but the rack rates were about the same for the entire month, and were an amount I was comfortable paying. By the time APH rates were released for our dates over 11 months later (just a couple of weeks before our trip) -- Universal had doubled the rack rates for that holiday week -- so that the few rooms that were offered at an APH rate were actually more expensive than the then-rack-rate room I'd booked a year earlier. Now, I always book a room as soon as I know our likely travel dates, so I have a reasonable rate locked in, in case the price surges later on. Of course, if a more attractive APH rate/room becomes available, I can always rebook at that rate, so it's a no harm no foul situation.
thank u
