beeb, you would be crazy to leave a U.S. major for an overseas deal unless you were being furloughed. It's honestly not worth it. There is a reason they are always advertising! The training in Japan is 9 months to one year which is just ridiculous. Have you sat on a jet for 12+hours every month after flying for twenty days? You can also be downgraded. You would regret the move after 6 months realizing you have possibly another six months of training. Have you read about the high failure rates in Japan or Asia or the Middle East?
Hang on to what you have for dear life. You won the lottery and now you want to give it back? Have you lost your mind???