At Google I/O 2016, Google said that they are adding the functionality of joining and leaving the beta programs of applications right from Play Store itself. However, they released an update after that which enabled this feature for some users and Google said that they reverted back the feature for a server side change. Thankfully, the latest Google Play Store 6.8.20 APK update has resolved that issue and beta testing is enabled for all.
The earlier Google Play Store APK update v6.7 had enabled the beta feature for some of the users and many were left out. Now, with the latest v6.8.20 update, users have been reporting that the beta testing feature has been enabled and is available in the latest Google Play Store APK download file. Many users may still not see the feature as it is a server side change and Google might still be busy with it.
That said, the new Google Play Store 6.8.20 APK download will slowly start to roll out and will reach your device in a couple of days. But if you can’t spend up the time waiting for the update, you can head over to APKPolice.com and download Google Play Store APK latest version.