It would not surprise me if there are change in EMH or hours before we go in March. However, the encourging thing is that the hours are not conservative. So they are less likely to add hours or showings as they are already open late (MK is open until 11 several nights) and there are double showings of Fantasmic and Spectro on several nights. And while they can shorten hours or remove showings, I don't think that they will unless there is a drastic downturn - i.e. a 9-11 type event.
Personally, I think someone new was put in charge of hours and is going at things in a whole new way. Instead of the cautious "I won't promise anything until you show me hard reservations for that date" approach that results in frequent changes as new, hard data is available, I think they are taking the "we've done this for years, we know what the crowds will be, so plan on it now" approach. So I think there will less changes, but there will still probably be some changes when they guess wrong.