Members of the armed services need special NIC rules to deal with their unusual circumstances.
Serving members of the British armed forces are always employed earners, even when posted overseas, as they are treated as present in the UK. EC Regulation 883/2004 makes them subject to UK rules wherever they serve in the EEA (art. 11(3)(d)). There are special provisions in the reciprocal agreement between the UK and Cyprus (governing the sovereign bases), and the UK–Germany bilateral agreement (which still apply as exceptions to EC Regulations).