Processor Sub Processor Agreement

For the prepaid airtime, all the prepaid airtime supplier deal with the supplier and service provider and supplier, we are all processor and sub-processor and it is bilateral way. how do we draft it in processor sub processor agreement? as we all could be both processor and sub processor at any time. we cant put it as A is a processor, B is a sub processor, however the relationship and status changed as A could be sub processor and B could be processor at anytime, as their identity or status always change due to bilateral. How should we identify both Party and draft it in the agreement? Please advise. Thanks