Susan Collins actually said...

if sequestration is not removed, the unit cost is going to go right back up

I know enough to defer to Senator Shelby on this issue regardless of who got here first.

If sequestration were to come back in 2016, what impact would it have on the unit cost of the F-35?

I totally share your belief that sequestration needs to go away permanently, and it would have devastating impacts if it does.