I don't have any first hand knowledge of the board dates, but just because you haven't heard anything does not mean there was not a board. NROTC only notifies candidates when they are selected for a scholarship. If you are reviewed on a board and not selected, your application is rolled over and considered again on the next board, but you won't receive any notification or status change. Around March, the board will start sending out notices to candidates that they were not selected for a scholarship. If you get one of those notices, it means you will not be considered on any remaining boards. From posts last year, NROTC runs multiple boards per month in March and April as they make their final selections.
Good luck.