@David Thielen You can move an app to another App Service plan, as long as the source plan and the target plan are in the same resource group and geographical region.
To elaborate, Azure deploys each new App Service plan into a deployment unit, internally called a webspace. Each region can have many webspaces, but your app can only move between plans that are created in the same webspace. All plans created with the same resource group and region combination are deployed into the same webspace.
For example, if you created a plan in resource group A and region B, then any plan you subsequently create in resource group A and region B is deployed into the same webspace. (Note that plans can’t move webspaces after they’re created, so you can’t move a plan into “the same webspace” as another plan by moving it to another resource group.)
Please refer to this article to know more: Move an app to another App Service plan
Hope this helps. Do let us know if you have further questions.
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