I am developing some paid for premium features for my plugin which is already available in the WP Repo.
What are the best ways to validate licensing etc. for premium features? I want to continue to use the repo so "calling home" is not an option as it is against plugin guidelines.
These features are to be purchased annually so there is an expiry to consider. I'm fine with the coding side of things, just looking for a best practice method to provide a license of type without users being able to manipulate the expiry date - I accept the date will be within the DB somewhere and I am fine with that - I trust the users not to manually change