The position of record determines the coverage. Therefore, an employee who has been detailed or temporarily promoted from a covered position to a non-covered position continues to be covered.

Conversely, an employee who is not in a primary or secondary position, and who is detailed or temporarily promoted to a primary or secondary position, is not covered under the special provisions.

CSRS and FERS Handbook, Chapter 46 (available on the OPM website. Also commentary in summary in Federal Register, Volume 52, No. 242, Thursday, December 17, 1987, page 47894.)