Well, yes and no.
Stroman is a lock for the rotation, dealing him unless for some fantasy just makes no sense.
Dickey is a lock for the rotation, whatever his value is is likely less then the 200IP he's good for next season.
Estrada is a lock for the rotation, he didn't re-sign to be a pen arm.
Happ is a lock for the rotation, he didn't sign to be a pen arm.
There's really only one spot open and that will be Chavez/Hutchinson or a FA as it is early, but, this rotation is essentially locked in imo. Either people like it or they don't, but, I'd say it's at least 80% locked in as of right now.