Although your replay is available immediately, it takes some time to appear in your YouTube Video Manager for downloading. The longer your JamSession is, the longer it will take for the video to encode and upload to YouTube. Generally it takes about as long as the session was (so a 90 minute webinar will appear around 90 minutes after it ends).
Even though YouTube is the fastest encoding around, it’s not instant. The lowest quality of video becomes available first (240p), and it takes longer for the 720p, 1080p, and 1280p versions to become available.
If after a few hours you still are unable to see your video in your Video Manager, perhaps it uploaded to a different YouTube channel than you anticipated. Go to your replay and click the “watch on YouTube” link in the bottom right corner of the video. This will show you the video in YouTube, and you’ll be able to see the account it was uploaded to.