I, too, am trying to plan our June trip and understand your frustration in not being able to plan without the park hours. We Moms don't have any "inside" knowledge to when they will be shared and find out along with the general public.
However, because of improvements being made to the reservation system, we can't currently make advanced dining reservations yet for places other than Chef Mickey's, Cinderella's Royal Table, and Victoria and Alberts. In fact I was actually on the phone with dining today, and the cast member thought calling back mid-to late January may be the time to begin making other reservations. Hopefully by then, the park hours will then be available.
If this helps, I can share you the trend (not guaranteed to be the same in June) of days when Extra Magic Hours are offered:
Magic Kingdom AM on Thursdays
Magic Kingdom PM on Sundays
Animal Kingdom AM on Mondays
Animal Kingdom PM on Wednesdays
Epcot AM on Tuesdays
Epcot PM on Fridays
DHS AM on Saturday (the PM EMH were more random)
This is what I've used to do my pre-planning for our trip and did book CRT and Chef Mickey's.