No, because in 90 minutes the cryogenic liquid oxygen would have warmed up too much. The Falcon doesn't have an onboard refrigeration unit; it relies on loading

No, because in 90 minutes the cryogenic liquid oxygen would have warmed up too much. The Falcon doesn't have an onboard refrigeration unit; it relies on loading the propellant shortly before launch. However, "shortly" is also relative, and 90 minutes is not long enough to purge all the fuel from the rocket and refuel it with cold oxygen (it took close to an hour today to de-fuel the rocket), so it can't be cycled in that window.