There are few Neffos models weaker than Neffos X1 Max and they already updated to NFUI8 - why X1 Max still isn't?

As the topic says, it would be nice that tp-link forums could have subforum for tp-link Neffos smartphones :)

I found out, that some Neffos smartphone models which are comparably as good as, but also some other are weaker than, Neffos X1 Max, already got updated their firmware to Android 8 Oreo. Why X1 Max...