Who's the agency? Suspect it would need to be a collective cooperative of the pilots. That needs cohesion & leadership, the lack of which has allowed this situation to develop in the first place.
But then again; the whole agency status is up for close inspection. A collective summer holiday unavailable for duty declaration might be effective. All my household contractors go on holiday in August. A plumber or electrician or builder is not possible. So why not also a self-employed pilot?