I just submitted another request about SyFy. It was the main reason I bought PlayOn and not only did the channel randomly disappear, but I can't get an explanation why. Not to mention that support auto-replies say "You'll hear back from a member of our support team staff within 48 hours." yet I've NEVER heard back about anything.
If you're going to drop channels at least let your users know. You have no problem letting us know when you fix a channel or add a new one, so what makes this so difficult?