Hey @TeamYouTube. Do you know why I can no longer add a private/scheduled video to a per-existing playlist while having it set as 'official playlist'?
I used to be able to do this. Now it says that I can't because the video is uploaded to a 'different channel', which is false.
If you're still experiencing this, send your feedback right away for review: https://yt.be/help/feedback . Hope this gets resolved soon.