https://orbxsystems.com/forum/topic/205734-london-city-pack-update-i-still-can-not-find-it/
https://orbxsystems.com/forum/topic/205761-when-to-expect-london-city-pack-v2-in-marketplace/
just two discussions over at ORBX forums. Seems to be out for customers who bought it directly with them. Asobo / Microsoft seem to take their time to upload a fix already provided by ORBX.
So, seems like I have to buy my next addons directly there…