Felt's FAQs say,

"CAN YOU HELP ME IDENTIFY THE MAKE AND MODEL OF MY FELT BIKE? I HAVE THE SERIAL NUMBER.

Your bike’s serial number may not necessarily point to its exact model or model year. But send us a photo of your bike and we’re happy to help identify it."

Finding a way to post a photo is going to be the easiest thing, or just ask Felt. The biggest delineation is where the rear brake is; if it's on the seat stays it's a 2013 model or earlier, and if it's on the underside of the frame near the bottom bracket/cranks, it's 2014 or later (don't think they've meaningfully updated the frame since).