This is a long thread and full of great information. For clarity: Is the BiaNow e-med test accepted for both the USVI entry from the mainland and the entry into the BVI from USVI?
For entry into the USVI from the mainland, YES.
For entry into the BVI from USVI, YES in my personal experience. NO according to emails from HSA requesting clarity. If you're concerned, get a Rapid Antigen test before travel to BVI.