Unable to read/write to Play Leaderboard

, I would like to write an updated and more thorough guide for users involving Play and leaderboard setup once I get this working.

I did have two questions that maybe you can answer:

A) Can you launch on mobile and have leaderboards work or must the APK be uploaded to the play store first? This is fairly important because there is roughly a four hour delay before you can access your projectper time you upload to the play store.

The Developer Console states (very conflicting information): “The following groups can test your saved drafts for Play game services before they are published.
You will also need to publish your android APK to Alpha Testing or Beta Testing.”

B) If you don’t need to upload your APK to test what is the bare minimum needed to test leaderboards and achievements?