Hi @RemiChambard2,
You would need to import a new managed solution that has the previous version of the app.
Alternatively, if your managed solution only included the App in it, you could simply just uninstall the solution and it would effectively remove that managed layer and the previous layer would take precedence. The problem is if you have other components in your solution such as Tables, would also get removed, and potentially result in data loss.
While its more often simpler to have a single solution, its not a bad idea to group Apps and Flows in their own solutions, separate from other core components.
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