Can I keep the same listing but change the package it provides?

Yes, you can change the managed packages that are linked to your listing. On the AppExchange home page, click the Publishing tab and log in using the credentials for your AppExchange Publishing Organization (APO). Click Your Organizations and then Link New Organization. Add the credentials for the Developer edition organization where your new managed package was created. This makes all listings and packages created by your Developer edition organization visible to your APO.

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