If an employee needs to miss a perfunctory status meeting in order to attend the birth of his child, you let him. If an actor needs to miss one episode of anybody-could-do-this-job pushing buttons and saying “Yes sir” in order to have a major part in the next film from a director whose last four films garnered 28 Academy Award nominations and won two Best Picture awards, you let him.
No you don't. I'm not actually making a judgment call one way or the other on this specific situation, I am just pointing this out: *by contract* the television show has the guarantee of an actor's services, whether that actor is actually in the episode or not. If they need you at the last minute, you get to the studio. You didn't have a contract to show up at every meeting. Missing a week of television production is not really analogous to that. Some producers in Hollywood are easy to work with and will write you out of several episodes at a time, and I hope if my career makes it that far I will be as accommodating. But contractually, they don't have to let you go anywhere.