The second phase of EMUI 12 has started, now they are looking for beta testers for these models, there is even the Mate 20 lite that was not in the official list
Huawei releases EMUI 10 beta (Android 10) update in more regions
EMUI 10 beta for Huawei Mate 20 Lite rolling out in Europe - Huawei Central
Just received EMUI 12 beta update today "Mate 20 Pro" : r/Huawei