The word "run" and "S-Boat" do not belong in the same sentence. Even "run" and "submarine" don't belong in the same sentence. The task force is good for 30 knots. What are you going to do? If you surface for more speed you'll have 30 guns on you in 5 seconds. You can't outrun shells.
So if they know where you are they are going to catch you. You're stuck with weaving and dodging until you can get to deep water. You have enough battery power for that? And how many DD's are you dealing with. I know I can dodge two in my Balao. Never tangled with three at a time. But the sugar boat in the real war was somewhat of a death trap. Wasn't a healthy command for a sub skipper and they mostly prayed they'd survive to command a more capable boat.
But there's your only available stategy: evasion with deep water being your goal. Use your periscope (like they don't know where you are anyway!

) to gather more information on occasion. And remember, this isn't hell! You're collecting stories for the Subvets conventions after the war.