Nursin board

I was turned into the nursing board for something about a year and a half ago. I first responded to this in the beginning with a complete explanation of the situation, and my innocence, in a letter to them. Since that time, to the present, I have recieved a letter from the board about every 3-4 months stating that they would eventually get to the investigation( I am paraphrasing).

Is this normal procedure for the board or is this an indicator of something else that I am not aware of? This is a first time for me dealing with the Nursing Board.

Thanks!