Your core question relates to how you can edit an app's permission after the app has been graduated and is in operation in production. The answer to that question, for the time being, is that you can't. Once an app has been graduated, we do not permit developers to edit anything related to the security settings of that app in order to protect users who made have already installed that app.
I created an idea in our ideas portal to change this behavior - which we have every intention of doing in the future. If you would like us to implement this feature, please vote for the idea at the URL below:
https://ideas.ringcentral.com/ideas/CUSTCOM-I-2552
Next, you asked about the Edit Accounts permission. This can be added to your app by an administrator. To request this permission, please login and contact our support team via our online form: https://developers.ringcentral.com/support/create-case
