The Anegada <-> Road Town ferry alternates bi-weekly between Smith's and RTFF.
Approximate schedule:
Anegada-Road Town - MWF 8:30am, 4:30pm
Road Town -> Anegada - MWF 6:45am, 3:00pm
I recall one company might leave at 7am instead of 6:45 and lately, the 4:30 boat is more like 5:30 but once you're there, you can just ask around and the residents will know for sure!
Expect the afternoon boats to be late due to cargo loading/unloading.