Pilots receive flying pay from the date that they are awarded their Army Wings until they leave the forces, get promoted above Colonel or are withdrawn from flying duties. After 5 years in a non-flying post the value starts to reduce eventually reaching nothing although a AAC MCM are normally very good at ensuring this never happens.
Door Gunners used to be only awarded flying pay on days that they actually flew. Some good work by DAAvn now means that permanent posts have been established and a formal career stream enabled which allows them to recieve flying pay as long as they are filling an established post.
Air Despatchers also get flying pay although I am unsure of the rules.