The old APK page is going to be removed soon from the Google play developer console. They introduce a new page - 'Manage releases'. I have moved to use the new page to manage releases but I cannot find where to manage the alpha and beta testers lists. It is currently still in the APK page, but when this one is removed I won't be able to change the lists... any idea?
When you click the Manage beta
or Manage alpha
buttons on the Manages releases page, the top section is labeled 'Manage testers' - clicking on the drop down in that section will allow you to change the beta testers list.
Keep in mind you need to publish your app first to share link to testers: