- 'Upgrade/downgrade to a specific version. CHANNEL and TAG defaults to '
- f'"{CHANNEL}" and "latest" respectively if omitted; See "UPDATE" for details. '
- f'Supported channels: {", ".join(UPDATE_SOURCES)}'))
+ 'Upgrade/downgrade to a specific version. CHANNEL can be a repository as well. '
+ f'CHANNEL and TAG default to "{CHANNEL.partition("@")[0]}" and "latest" respectively if omitted; '
+ f'See "UPDATE" for details. Supported channels: {", ".join(UPDATE_SOURCES)}'))