I feel like we are all idiots repeating "space is expanding" if humans could live 14billion years in age, and we were present when it started, but we left good old Bob on the part of the universe that was travelling away from us, he would have traveled FTL from us. Even if you said space expanded, the traveling has been accomplished. So now we know that space expansion is how you travel FTL.
In other words if humans ever invent warp, the space expansion work around we would effectively have FTL travel.