This really makes me doubt whether or not I should book in the BVI's for April 2021. I have a credit with Sunsail from April 2020 that I was planning to use next year. And while I can wrap my head around testing requirements, the quarantine and not being able to book airfare into EIS until 5 days prior are deal breakers. I have my flights into STT already, and would entertain a puddle jumper to EIS if I had to, but not being able to book until last minute is worrisome. Also, if I had already rebooked for next April but decided that the quarantine and other entry requirements were really too tough to make it worthwhile, would I be eligible for rebooking with no penalty since the BVI's would technically be open? I think I'll hang on to my credit a little longer and entertain other Sunsail destinations as an alternative.
I think the seaports being closed will be very short term. There will be too much volume for the airport and too much pressure from the ferry companies. The Premier has stated they would release the planned opening dates in the next couple of weeks so if you can wait that long, I think your issue will be resolved. My guess is January or February 1 for ferries.