It obviously doesn’t change the height. But there seems to be other thing going on as well:
”In gravel mode, the ride height is raised by 30 millimetres compared with the sedan. Gravel mode also influences the Porsche Active Suspension Management (PASM), Porsche Traction Management (PTM)...
Useful info, thanks.
This means that the offroad package doesn't really give any different options compared to the standard, it only sets the default to the gravel mode. The reasons for taking the offroad package are even less than I thought (good I decided against it).