Fascination - formal night/s?

We are to be on the Fascination the end of March next year. Someone may have posted this answer, but I haven't seen it.

If you have been on the Fascination leaving San Juan and done the 7 day cruise with only 1 sea day, could you tell me what night/s are the formal night/s?

When I went in May, the formal nights were Tuesday and Thursday (on my sailing the first was Antigua, but that's also a sea day on some sailings). The other is the St. Lucia day.

Thank you. Even though we are leaving from San Juan, Tuesday is our sea day, so that may apply to the formal night as well.:)