Did a few more tests. I started at around 6:45 Zulu at EDJA and started moving around in weather using slew mode.
What I saw was some beautiful overcast…
Climbing up I saw double layer cloud front with connecting cumulus towers. While this might not be very natural looking, I remember seeing this often pre SU7, when weather was still multi-layered.
Look at that smooth beautiful overcast again, but a few kilometers away, with blue skies above
Then 07:05 happened, and the weather turned into this pretty much everywhere:
Whats interesting: EDJAs METAR still reported Overcast. The sim drew a circular pattern around the airport with respectable looking overcast (of course made up of cb clouds). However, the cloud base and percipitation changed and jumped every half hour exactly on time with the automatic METAR updates, while the Meteoblue forecast model predicted no relevant change during that time. So what the Devs said about METAR not having an influence on clouds at all is pretty much bull in my eyes.
EDIT: Removed pictures name with timestamp to avoid confusion, as the time shown was that of me cropping the pictures and saving as copies, not their time of creation.