Timeline updated There's a few points still not matching, but after I fix those, all the rest should work!
The problem is figuring how quickly the WaveDancers pips age!
Right now we have the following to work on. Sunstream is 18 when he Recognized Brill, and she says that Tumble, Puffer and Moonmirror are (physically) "older than him". That could make them any age from 20 to 40, or even older...
... because in Wavelet's recollection, she says that ""After the battle, he (Perith) brought me here and raised me along with his other children. <...> But one day, when Perith's son was an old man, I found that I could make plants grow and bear fruit with a touch. Since that day, the village has called me Good Spirit of Plenty."
And the flashback shows her as being very young, barely a teen. Now, we don't know how old Perith's son was at the time of Wavelet's birth - she says "Perith had a son, and that son had a son". Does we have to take it litterally and assume that his son was born after her - something she witnessed - or merely her way of explaining to Windkin and Wavecatcher how long she's been alive, by human generations (possibly the only way of "counting" she knew)?
I guess we'll figure out more when we see Korafay in Final Quest - she should be roughly 40-odd. Chitter acts and looks like a young adult, but she's a Wolfrider. I wonder if Korafay, born within few years from her, will look older or younger - and especially how tall, compared to her parents. That would take me a step closer to figure out the ages of the Crest Point pips, and of Wavelet when she discovered her talents.
In the preview pages for issue #1, Sunstream says she's "well grown"... though we don't know to what extent yet. He might just mean that she's not a baby anymore and he feels confident leaving her, and the WaveDancers, for longer time to carry out his duty. Or he could litterally mean that she's grown-up like Chitter - we'll just have to wait and see!
(Of course, this also brings up the question of how old she is psychically. Her father at 18 was already responsible and "grown up" in his own way, so Korafay might take after him being the next "child prodigy". But it might not be the same for all WaveDancers kids.