First upload with spatial audio
Finally, finally, finally! The upload on Youtube with 4 channels for spatial audio worked!!!!!!!!!!!!!!!! By now spatial audio only works using headphones on the YouTube Android app (Android version 4.2 or higher) and Chrome, Firefox, Safari, or Edge desktop browsers.
More to come in the next project of TrackRecord @@
You can read the process and conclusions of the whole process here: The main lesson we learned about recording spatial audio is probably old — but still valuable.