In the case we have a channel update, which of course has to go through Roku approval, and is released once approved, what if that update involves a schema change in our backend database web services?...
I've run into this a number of times. Usually we end up either adding a version parameter to the API calls, or we move the API endpoint altogether and leave the legacy API endpoint up for a few weeks after publishing. Another option would be to build update detection into the channel, so the channel checks at launch and let's the user know if they need to update the channel manually or not.