How long is the air force cross training window opened?
The retraining window for four-year enlistees is between 35 and
43 months time in service and for six-year enlistees it's between
59 and 67 months. However, at an overseas location like Incirlik,
the retraining window shifts.
If you're overseas, the retraining window is 15 to nine months
prior to an Airmen's DEROS as long as they enter their normal
retraining window prior to PCS.
You can get more information on the AF Portal.