I was thinking what happened to the P20 series that nothing was mentioned about EMUI 12 since the official list was released at the end of October but it seems that in
Huawei P20 Pro CLT-L09 Orange EMUI 12 Update Installation(C109)
EMUI 12: A game changer for global Huawei phones - Huawei Central
HUAWEI P20 EMUI-12 RUNNING!!! EML-L29 - YouTube
What I don't like about EMUI 12 for Huawei P20 Pro? - YouTube