Fair to say that many justifiably assumed "subject to change" referred to the hours of operation, not availability in its entirety.
I get that they're realizing the coaster can't process all of the Express guests in the time it's likely to be open during the event (which is its own major problem), but one, the theoretical ride capacity wasn't a surprise, and two, when you backtrack like this, it's good service to make it up to your customers willing to shell out for the premium experience. This "you should've read the fine print" shrug of a response is a terrible look.
...and I'm saying that as someone who's 1) already been on the ride and 2) is attending on a RIP tour! I'm not affected!