Craig Steele, on 03 April 2014 - 09:54 PM, said:
Wolf Dragoons supposedly 'abandon' their mission sometime around 3039 when they stopped sending reports back to Clan space.
Field Manual Mercenaries details their decision not to return to Clan Space to rebuild after the 4th succession war as they feared being 'ordered' to stay in Clan Space and they had already decided by then they would fight against the Clans. There is no date though next to this description.
There is something somewhere about he Clans hearing about 3039 from Wolf Dragoons but I can't lay my hands on that source atm. But there are no subsequent reports back to Clan space AFAIK.
Deduction is therefore around 3039?
So therefore the Dragoons would be the most appropriate unit for IS freeborns who pilot clan mechs.