I know of no other business that posts its operating hours months in advance. Disney has always done this for the convenience of its guests, but they have no obligation to do so.
What do you mean? My local Target store has their hours posted and they haven't changed in years. Most stores post their hours and you can count on those hours not changing for years. They don't post that their hours are only good for the next three months and then release some new hours.
Disney has been in this business long enough to know how their business operates. They can probably predict fairly close many years in advance what their park hours will be. Their hours change seasonally and are probably on a pretty consistent schedule.
There would have to be some pretty serious cutbacks for me not to feel this way when I go in 2 weeks (from today!). 
but we will survive.

Honestly ~ I really could care less about the hours. again JMHO!
for her first trip to Disney!!
Hoping it was just an oversite, I called CR and was advised per their calendar, NO performances of WISHES have been scheduled,
and we are talking about the weekend also.

to utilize our days to their fullest! 