I think that they may want them sooner rather than later, so a 20 year development program may not be the answer in the short term.Well if the USAF thinks it needs to increase its heavy airlift capability then perhaps speeding up the development of a new lifter with some stealth features makes more sense along with a modified version for tanker service. From a selfish POV, restarting C-17 production might allow the RCAF to acquire 2-3 more.