Best way to notify WordPress plugin users of new release candidates for beta testing?

Over the years I have developed a few WordPress plugins for my own use and shared some via the WordPress.org plugins directory. I have recently made some changes to one of my shared plugins and would like to share the updates but I don’t want to risk breaking a website that uses it. I believe the best testers would be those who are currently using the plugin. But, while WordPress does provide a mechanism for automatically notifying plugin users that new versions of a plugin are available for update, to the best of my knowledge there is no mechanism for notifying plugin users that release candidates are available for testing.

I was thinking that I could develop a process that would check a pre-determined URL for notification messages at a pre-determined interval (something like once per day or once per week). I would run this process during plugin load if the user can manage options. I could then present any notification messages that were returned from the most recent check until they are dismissed. But why develop it if something already exists or if it would not be considered an acceptable practice?

So, my question is: is there a best practice or acceptable practice for plugin developers to send notifications to site administrators of sites using the plugin?

After no answers for a long-term solution, I have developed a solution called the WP247 Extension Notification System. It is comprised of two plugins that are in the WordPress plugin directory:

• A “Server” plugin called WP247 Extension Notification Server that runs on the extension developer’s website to compose and distribute notices.
• A “Client” plugin called WP247 Extension Notification Client that runs on the extension user’s website to retrieve, display, and dismiss notices.

See this article on the WP247 Extension Notification System for more information on how it works.

That handles the notification side of things. I ran across this article called Beta Testing WordPress Plugins with WP-Rollback and will use this approach for beta and release candidate testing going forward.