Yes, then as others stated Deathwing flew to it and the red dragons started guarding it. But come cataclysm it's going to change ownership once more and become Twilight Hammer controlled.Originally Posted by Nienniora
So it went Dwarf -> Horde/Enslaved Alexstrasza -> Red Dragonflight Takeover (when Rhonin frees Alexstrasza) -> Twilight.
I'm saying the last thing it was, was the red dragons had control. Though you can help answer for me when did Sinestra make the twilight dragons. As in that time-frame I can only see her doing it during the part when horde has control. Which would make sense as she is taking then the imprisoned Alextrasza for the dragonflight eggs plus this leaves the time for when the Nether Drakes are born in outlands already and Zzeraku tries to escape through the dark portal when it opens and gets captured. Then later the portal is destroyed and Alextrasza is rescued.