How long after BA (above muscle) to start running?

Thank you for your question. You definitely want to follow your own surgeon's post-op activity instructions. This is a general guide I give to my patients:
1) No heavy lifting or strenuous activity for 6 weeks.
2) Resume walking at a leisurely pace right after surgery (e.g. 2 mph)
3) At 2 weeks, you can walk 2 miles at 2mph
4) At 3 weeks, you can walk 3 miles at 3mph
5) At 4 weeks, you can walk 4 miles at 4mph
6) At 5 weeks, you can jog 5 miles at 5mph
7) At 6 weeks, you can resume all activities, but listen to your body and use discomfort or tightness as a guide so you don't over do it.

 In patients that if healed properly I permit running it for weeks with a good athletic bra. However, you should get your instructions specifically from your own surgeon.

I would recommend asking your surgeon about activity in your particular case as i t can vary. I tell my breast implant patients not to exercise at all for 2 weeks. Then they gradually increase activity. After six weeks, I tell them to resolve just about all activity. I prefer they avoid push-ups and bench press for many months after surgery.