@TeamYouTube what's going on? I got up just now and went to watch YouTube, only to discover that I'd been unsubscribed from nearly half of my subscriptions? Can you reverse this?
We don't auto unsub users. If you're using a shared computer/device, consider signing out of any Google services when not in use. It is possible that you're still signed in while someone else browsed through YouTube and made changes. If you notice anything else, let us know.