If your feed provider isn't currently supported or you have your own provider you're not out of luck!
During the onboarding & upgrade process you will have the option to request a new feed provider setup. If we determine that the integration with the new provider is feasible we will typically assign a 2 week turnaround upon acceptance but reserve the option to adjust that timeframe based on the complexity of the integration.
Keep in mind that each provider is like a new mini-development project so please be patient as we work through the process of getting the integration right with the provider.
Reference the article below for more information on the feed provider setup process:
Inventory Setup & Schema Details for New Providers