Most Whipples are undertaken for malignancy so you may be a little faster but it will be months. I would recommend you consider resistance exercises beforehand and a high protein diet to build .up muscle mass.
There are obviously a lot of possibilities and I would not wish to speculate to time to flying
I would confirm you should not have this done in Dubai. The surgeon is only one part of a team and I would advise a proper hepatobiliary unit. The surgeon should not be undertaking any surgery except pancreas, liver and bile duct - if he does other things he is not specialised
Also ensure the funding is in place in the US not only for the operation but also for any complications or prolonged stays in ITU. This would not be a problem in the UK where there are a dozen or more world leading centres