i think I understand the OP's question as whether or not SIM AI will recruit after humans start recruiting. The answer is no and yes..... SIM AI does the majority of their recruiting pre-human recruiting. So if you knock them off before signings start and are the only team they are considering, they are yours once signings begin because SIM AI will not pop back up into consideration.
SIM AI will begin recruiting again a day or so after signings begin and can take players that no one is recruiting and could possibly pop up on someone you are recruiting, but normally are not hard to beat on their second wave of recruiting.
When I played GD, SIM AI recruiting continues the whole time, but in HD they only recruit a couple waves of recruiting.