Khrysalis came out in two parts, the first in the autumn and part two came out the following April. Going by that, I'd guess part two of Empyrea might be released within the next couple of months.
It's coming. I know we're all excited but try to be patient. If KI rushes to creating worlds, the world is not going to be a good one to quest through it.
I guess we will find out reall soon. If Ki starts releasing teasers this month or next month we'll have a Spring release, if not we will most likely see it late Summer or early Fall.