Final answer:
The question is about the Stripes for Exceptional Performers (STEP) program in the Air Force and the limitations on promotions.
Step-by-step explanation:
The subject of this question is Military, specifically the Air Force. The question refers to the Stripes for Exceptional Performers (STEP) program that is implemented in the Air Force.
Under the STEP program, airmen are eligible for promotion based on exceptional performance. However, according to the question, an airman cannot be promoted more than once during any 12-month period under any combination of promotion programs, except for certain exemptions.
To fully understand the exceptions and specific details of the STEP program, it is recommended to consult official Air Force guidelines and policies.