I don’t know the answer to that question, as a matter of fact, to be honest.
However if one accepts the definition of “bastard child” as one concieved as a result of willful fornication I would say “no”, as, at the time, (I think it’s safe to assume) the two believed they were married so they did not “willfully” commit fornication.
This is my opinion of the situation.
Ok. I was always curious about that.