A hold or avail in casting and acting is when casting/client is interested in hiring you. It’s a common practice to make sure you’re available for the dates they plan to have you at the set. One of the difficult realities is to be taking off avail or hold. One of the most unprofessional circumstances is when casting/client doesn’t take you off avail/hold when they have made their decisions. The reason is that as an actor you are on hold for those dates which means you are not available to take another job. Your agent will call to confirm if you get another offer but as a courtesy, those dates are unavailable until you are released. Since this has happened to me on several occasions, my suggestion to you is always have your agent double-check.
SAG-AFTRA