Honor 5X (Kiwi) Upgrade a 0.12-nougat to 0.10-pie possible

Hi, I have a Honor 5X running e-0.12 from nougat branch.
Apparantly there is pie support now but the latest image is of version 0.10 for pie.
So the obvious question if this is supported or what should I expect if going through with it?
I am planning on doing a full TWRP backup beforehand as recommended anyway.
Has anyone done such a down/upgrade?
Can I go back to 0.10-nougat and if yes, where are the old images?

regards

Steffen