TSA modified the definition of “stopover” to make a distinction not only between domestic and foreign travel, but to recognize that non-continental U.S. air transportation (outside the contiguous 48 states) is more like foreign air transportation than continental air transportation. Stopover means a break in travel of more than:

• four hours (4) for continental interstate and intrastate air transportation
• twelve hours (12) for non-continental interstate and intrastate air transportation as well as foreign air transportation.