Can a marine reservist become an air force officer before his contract ends?

Well, hello there weekend warrior. Kidding. What you should do is talk to the AF recruiter. That'd be the first step. As far as going before the end of your contract, no. You'll have to finish the contract. I do believe there is a psych eval and a wait time. Not 100% sure about that because I chose to stay motivated, stay enlisted and stay Marine Corps. Good luck getting in though, it'll be a better life style.