If the arbitrator chooses to honor the Frontier LOA, then the C-series will go on the F9 certificate. There is almost no chance of this happening though. Its a last ditch effort by FAPA to come out on top in this thing. The arbitrator COULD delay implementation until a common contract is ratified. If thats the case, 2015 may be aiming high. The company will drag their feet for 10 years on a new contract if they're able.

A side note: The republic contract would REQUIRE the C-series or any new aircraft be flown by those on the chq seniority list. The F9 LOA would require those planes be flown by F9 due to the weight. Its just a fact that this will turn into a big mess and we'll all lose in the end.