The Proposal API will be going away when the new proposal tool is released. Proposals will be moved under the order API. Please use the Order API and add an external id to an order.
The external Id allows API partners to store their unique Id on a proposal and correlate it back to a sold order. The API partner needs to create a link out from their system to AdCellerrant, which will allow a user to complete a proposal in AdCellerant.
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