Jackie, that is an interesting question.  Looking  online we see  FBI reports on the number of hate crimes directed against Muslims going back to at least 2001.  However, for the   2014 FBI report on 2013 I found the statement below which suggests they didn't start using  all these categories until January 1, 2015, as you stated. Could this be from re-analysis of data, or adding new religions to those they already used?
While I don't think this article was "made  up" I admit I'm puzzled and looking  for an answer. 

"Upcoming changes to Hate Crime Statistics: The FBI approved a recommendation by the Criminal Justice Information Services Division’s Advisory Policy Board to expand the bias types in the religious category to include all the religions identified by the Pew Research Center and the U.S. Census Bureau. Also, the hate crime data collection procedures will be modified to include an anti-Arab bias motivation. The collecting of both types of data will begin on January 1, 2015."