Rollback a specific service in a stack

I have a stack and 3 different services inside. A rollback from the UI is possible only during an active upgrade, so if I want to rollback at a later point, I can’t do it from the UI. I have to do it from the CLI.
In the CLI I try this:

rancher up -s my_stack --rollback my_service

but it responds with FATA[0000] No such service: my_service. If I try with:

rancher up -s my_stack/my_service --rollback

or

rancher up -s my_service --rollback

then it creates a new stack called my_stack-my_service or my_service.

It’s not in the UI because what you’re trying to do doesn’t exist, regardless of how you try and call it.

The rollback action is only available after calling upgrade and before finishing it.