It differs from person to person I think.
Depending on the length of the A and the time lapse between Dday and the actual 'act' it can be hard for some WS's to account for every second of their A which has a rebound effect upon their BS.
I no longer ask any questions as I am satisfied I have all the knowledge *I* needed to help me heal.
That is different to having all the answers I guess but I have what I believe to be the entire story.
What I do know is I know enough that I no longer have doubts.
You will know when you have enough information to help you move forwards.
ETA: It all depends on how transparent your WS is too.