According to the folks at WDWMagic.com, Disney is expected to soon announce some additions to the attractions that will be open during morning Extra Magic Hours at the Magic Kingdom. The list of the new attractions joining the morning EMH list are Big Thunder Mountain, Splash Mountain, Mad Hatter's Tea Party and Snow White's Scary Adventures.
The suspected reason for this addition is due to the impending long-term closure of Space Mountain and the Tomorrowland Transit Authority for their much anticipated refurbishments, which begin on Sunday the 19th.
The TTA is expected to open sometime in late summer while Space Mountain is expected to re-open just before Thanksgiving.
I'm glad to see Big Thunder and Splash Mountain are on that list. I've wondered why two of the big three attractions at the Magic Kingdom weren't open for morning Extra Magic Hours.