As has been said, friends don't let friends fly InterCaribbean. Sorry you had to find out this way. Glad you followed up because I have never heard of them helping or rebooking anyone, quite the contrary. Which is not to say people haven't flown them successfully.
Maybe they start in Providenciales, stop in the DR, fly to Tortola and possibly on to Antigua and return. It is easy to cancel the whole route, unlike US carriers whose planes and crews fly all over. It would be much better to cancel low season flights, or only fly one day/week.
We were surprised, and pleased, that American kept their schedule throughout low season. They had some great prices, too. Maybe they are eating into other carriers business.