Thanks for the pointer. Just looked. This announcement [1] says the rk3566a, which isn't quite as fancy. Still looks like a nice board. People on the message boards back in March [2] were guessing there won't be an rk3399-based Pine64 until early 2022. :-(

[1] https://www.pine64.org/2020/11/15/november-update-kde-pineph...

[2] https://forum.pine64.org/showthread.php?tid=9382&pid=61929#p...