I just watched the Disney planning dvd and it said that evening emh's are UP TO 3 hours. Then I checked the Disney website and it has the hours listed but does not say how many hours it is. How do I find out whether EMH's are 1, 2 or 3 hours?
Go with the plan that the evening EMH's are 3 hours long. The only reason they wouldn't be three hours long is if there is a special event that "rents" out the park, but 99% of the time, evening EMHs are three hours long.
When we were there in January all of our evening EMH's were only 2 hours long. I would go in assuming for 3 and if it is not three it will be posted at the location when you are getting your wrist bracelet.