Lost reverse in 200r4 . what happened?

[1981silverz28]

I have a 200r4 in my Camaro now,it was built by the local Chevy dealer with a B&M kit.1st through o/d is great.I put it in reverse last night and everything was fine,put in reverse this A.M. and there was nothing there,no slipping,grinding .nothing .It is just like neutral,I shifted the lever in and out of neutral and park,nothing .Is this a sign that the trans gods are about to claim my 200 or is this something that can be easily fixed.I also have a 3000 stall if that makes a difference.I posted up before about a stronger built trans ,I may need one sooner than I planned.