With the flight change you should be eligible for a refund. Rebook on another carrier. If you choose the STT ferry option let me explain the process going home.
1. Cab to Roadtown ferry dock.
2. Discover planned ferry canceled
3. Stand in long line in sun for different ferry. Pay double the local rate.
4. Stand in line to pay exit taxes.
5. Stand in line for ferry security which is a joke.
6. Discover ferry at least an hour late.
7. Stand in line to board.
8. Arrive STT and circle while another ferry unloads.
9. Stand in line to get off ferry.
10. Stand in long line for customs with the added benefit of getting gassed by boat exhaust the first 10 minutes.
11. Cab to airport.
12. Stand in line to check bags
13. Stand in line for customs again. Long slow line.
14. Stand in line to handover checked bags to screening.
15. Stand in long be line for security. Slow moving line.
16. Stand in line to board aircraft. AC inop in terminal.
17. Board aircraft. Never so happy to be wedged into airline seat even though hot, sweaty and thirsty!
18. 5’2” blonde discusses divorce during flight home!

Flying to SJU option.
1. Cab ride to EIS airport
2. Stand in short line to checkin and check bags.
3. Short security line into room with AC.
4. Walk out and quickly board.
5. Arrive SJU, Quick customs and immigration with AC.
7. Have decent meal at airport with AC.
8. Board flight home.
9. Discuss wonderful vacation during flight with 5’2” blonde. Plan to come back soon.