If I assault and cause more casualties, so I win, but in doing so have no more soldiers in my main squad, does a supporting squad get to move in?

And if I assault and cause more casualties, so I win, but I get wiped out, does the defender still have to retreat?

Dan said:

Yes,p.32, #10.

Dan said:

Yes, p.32, #9.

Though only if the supporting squad is still fresh.