[NX505J] I just don't get it -- why no FOTA ?

Hey guys,
Was wondering lately - there are lots of new firmware updates for the Nubia Z7 Max (started with 3.09...3.22...and now 3.55...)
I just dont get it -- why I don't get this updates via FOTA? why do we have to flash them?
I'm currently running the official 3.22 firmware with GAPPS installed.

Thanks! :cool: