A cross-platform management system that handles cross-platform management of client requirements receives a request corresponding to a plurality of client-defined requirements to be achieved in a flight. The request for the plurality of client-defined requirements is associated with one or more request parameters. The system generates a proposal plan corresponding to the received request based on adjustment of the one or more request parameters. The proposal plan corresponds to at least a distribution of target audience across a set of delivery platforms. The system executes the generated proposal plan for a first time period in the flight on one or more delivery platforms. The system re-optimizes the generated proposal plan and controls execution of the generated proposal plan for a second time period in the flight by an in-flight re-distribution of the target audience across one or more delivery platforms of the set of delivery platforms.