How likely is it that babies will turn ?

Hey guys well to explain, pregnant with twins and they've been head down mainly entire pregnancy (at least A has) but three weeks ago, baby A flipped and today is still not head down. They're both pretty much breech but curled like to the side with heads together if that makes sense. I'm 34+2 and the doctor said they seem comfortable if this is their chosen position and sometimes at this point in pregnancy, won't flip back but it's not impossible. He wants to give me a c-section if they don't flip head down soon. This hasn't happened to me before I've had 3 successful vaginal births. I really don't want a c-section unless it's absolutely necessary and even then I really just want to have another vaginal birth for many reasons. My question is from y'all's experience especially anyone with twins how likely is it that at this far along they'll flip into head down position? With one , I was never worried about it this soon cuz of course there's more room for their turning. They're already 6.9 & 7.3 pounds and harder to see and measure on ultrasound since they're smushed. He said there's nothing I can do about it (stretches exercise etc ) to help change their position.