Ahrensbach is also unusual in its current Aub situation. I think if it hadn't been for the purge he would have already retired.

I think the ideal set up of an Archduke family is

Former Aub- age 50 or 60 and up

Current Aub- taking office between the ages of 30 and 40 and ruling until 50 or 60

Heir- 15 to 30: chosen after all or at least most of 1st wife's children have either graduated or at least entered RA. Other siblings would be married out or pushed down once selected (except maybe support or spare)

Children of Heir- Heir to Aub probably encouraged to have children before taking the Aub postion so they can can more fully dedicate their mana when in office.

Under this structure the current Aub can be supported by both the previous and next Aub. Easing the training and passing of information.