Docker post arguments results in 'Execution error No such container'

For one of my Docker containers I have the following 'Post arguments' set:

&& docker network connect br1 home-assistant

When this is set and I stop and then start the array or docker service the container fails to start automatically.

If I then try and start it manually I get the error "Execution error No such container". I have to modify the container and hit apply for unraid to recreate it and start it. If I remove the Post Arguments then the container starts with the array no problem.