Complex sentence: Thereafter, Luftwaffe service personnel who had already been awarded the Pilot's Badge and Observer's Badge could qualify for the Pilot/Observer Badge; after 1944 the recipient had to have held both qualification certificates for at least one year.
Split into simpler sentences: Thereafter, Luftwaffe service personnel who had already been awarded the Pilot's Badge and Observer's Badge could qualify for the Pilot/Observer Badge. After 1944 the recipient had to have held both qualification certificates for at least one year.