From the opening of Pandora on May 27 through July 4, Disney offered Extra Magic Hours of 11 p.m. until 1 a.m. at Disney Animal Kingdom.
From July 5, the park hours will be 9 am to 10 pm, with evening EMH operating from 10 pm to midnight daily. An additional Rivers of Light showing has also been added with showtimes at 9:15 pm and 10:30 pm.
After that date, evening Extra Magic Hours will continue nightly through Aug. 19, 2017, but they will take place from 10 p.m. until 12 a.m. (midnight).
Not that it should be news, but Extra Magic Hours are only available to Guests staying in Walt Disney World Resort hotels. Please, check the schedule of operating hours to stay up-to-date on any changes that may occur with only Pandora being open some evenings and all of Animal Kingdom being open others.