hey there,
yes, the switch back option will be available in production too, this is how we'd like to support the transition period - we want to make sure that everyone has a chance to review the changes and accommodate to it. We're keeping the switch back option until we fix reported issues - as we expect more to come after prod release.
For Canvas features documentation is provided by production release - that is also on our radar and will be available on Saturday, when the release is scheduled for.