Replenish mercenaries

[Vercingetorix_the_11]

Good morning all
Is there a way to replenish mercenaries in a settlement, using the retrain option? I’m assuming there needs to be the merc unit available to recruit in the arrear. Any ideas compares.

[AveCaesar]

If you make the unit recruitable by your faction as well as being a mercenary unit you can do it. It would have to be tied to a building. I have the Sarmatian Mercenaries recruitable in Britain as units after Rome has conquered and reached a certain Stables level (I forget what it is at this time).