Bernd
Everything you said is correct but
Stick centered means, bank angle stays where it is up to 33 degrees, or returns to 33 degrees if it was more.
Is not quite the full story with the stick central if a gust upsets the attitude the bus will hold the new attitude and the pilot must still use the stick to
return to wings level. Keeping the stck central does not mean the wings will be leveled for you only that you have asked for not change in roll rate (rate = 0)