Schedule a job from the build parameters instead of setting up a trigger

I have a build config that is set up to deploy to a particular VM on a weekly schedule.

This weekend I want to deploy it to the normal VM but also to another one.

I can change the host in the Parameters if I do a custom Run but I can't seem to make the custom build run at a specified point in the future.

This is similar to this old stackoverflow question

The only way I can see how to do it right now is to duplicate the build config, modify the parameters and add a schedule trigger then delete it on Monday.

Or come into work on Sunday night!