On all factory xenons, not just bixenons you must set it into mot mode then manually adjust the headlights to mot spec, just slide by an mot bay, slip them a fiver & set mot mode get them to check the levels & then when done just turn mot mode of, simple & completely to road legal heights, trust me done myself few times.
As for learning the correct height, it doesnt learn this, all you're doing is saying please set the motors to a middle of road position or whatever audi have set as the position for the motors when manual adjusting, then it just auto adjusts the heights dependent on car level via sensors after you've adjusted the heights manually.
The levelling system never learns anything mate, sorry its not that complex & you'd think even with the adaptive bixenon like mine swinging left/right they would be able to auto switch to europe driving sides etc, no way hoozay you also have to lower them to what is known as tourist mode in vag, this just lowers the beam & also to add there are different part numbrs for each country even if they're adaptives, audi in there wisdom didnt think maybe we should make one type of adaptive headlight that can be used for any country & just have them adjust via coding, far to sensible, lets double our costs & make different ones for different countries, idiots.
I see so much money can be saved in developement & manufacturing if they just had a bit more thought in the processes.