Hopefully this will answer some of the questions
The regulations that will appear in JSP 752: Tri-Service Regulations for Allowances:
CHAPTER 10 SECTION 11
OPERATIONAL ALLOWANCE – INTERIM REGULATIONS
1
GENERAL
10.1101. Aim. The aim of the Operational Allowance is to recognise the significantly increased and enduring nature of the danger in specified operational locations (SOL), over and above that compensated for within the X Factor.
ENTITLEMENT
10.1106. Scope. The Operational Allowance is paid for each day that eligible Service personnel are in a SOL where the Allowance has been declared as payable. The geographical boundary includes personnel serving on RN ships in specified waters and those flying sorties over or into a designated operational area, provided that they directly support the operation. Detailed eligibility for aircrews will be issued separately. The intent is that those aircrew deployed to a forward operating base and flying regular sorties into the SOL will be paid the Allowance as if they were in a SOL. The intent for those who operate from the UK is that they will also be eligible for payment, but only at the daily rate, for times when they fly into or over the SOL in direct support of operations.
Seems fairly black and white to me