Runnells reports his faith crisis began in February 2012 on Mormon Stories Interview.
"Mormon Stories 480: Jeremy Runnells Pt 1 - On Growing Up Mormon and the Genesis of the CES Letter," Youtube, June 21, 2014
Jeremy: So, yeah...that year, it was a struggle.
John: So, that's 2012 to 2013?
Jeremy: Yeah, so my faith crisis started in February 2012 and then just to give you an idea, I published the CES Letter in April 2013.
35:13-35:33