I was looking around Pan Am's site earlier and I noticed that STI's had been added to the reservation drop down. I did a few searches and from what I can tell, service starts March 1st.
It looks like they'll be weekday (M-F) flights to BQN and SJU on BMA.
Monday and Friday flights to SFB via SJU and to PSM via both SJU and SFB. The STI-SJU parts look like they'll be on BMA.