What is the fourth series of Warriors by Erin Hunter going to be called?

Warriors: Book 1The Fourth Apprentice, Book 2 Fading Echoes , Book 3 Night Whispers
After the Power of Three Long Shadows and after another book of Power of Three [Sunrise] then the new series will come out (The Fourth Apprentice), but it is something about Firestar's kin (as always)

I would like to add that she has changed the name of the series, as quoted from wikipedia:

"The fourth, and not the final, series has been renamed as Omen of the Stars. The former series title The Fourth Apprentice will now be used as the title of the first book, instead of the former Book 1 title, Ambush. The series will be a direct continuation from Power of Three. [2] Like the three series before, this series will have six books."