Done the direct trip from CYOA to Francis Bay (and vice versa) a few times. It's about 13.5 nm and doable in 2 hrs with calmer seas, but plan for 2.5 hrs if you have strong E-to-SE winds and associated swell. Park Service advertises 57 mooring balls in Francis/Maho and I've never seen them all occupied in January.

If you're running short of daylight, it's only 7 nm to Christmas Cove with many free mooring balls though twice this winter there only 1-2 unoccupied when I arrived. I've not tried to anchor there yet.

It's 10.2 nm to Lind Pt/Caneel Bay where there are 40+ mooring balls. It's a reasonably calm anchorage after 6 pm when the daytrip power boat and ferry traffic subsides.