While you need to adapt your writing style for screenwriting, you also need to realize there are additional production steps to recording an on hold message. You need to find someone who has the right voice for the job, and who can read your script well.
The first step is to realize that writing a script isn’t like writing an article or any other kind of copy. Most kinds of writing are meant to be silently read by a single person. Yet, writing scripts is different because it’s meant to be read out loud by a specific person.

Of those businesses that responded, 85% would recommend on hold messaging and believe it's a useful marketing tool that adds value to the business. They rated on hold marketing as effective as Internet, TV/Radio, Direct Mail, and Print marketing.
The decision to update your on-hold message depends largely on the content you are sharing. If you are sharing content that includes short-term promotions, this information will need frequent updating so consumers are always aware of the status of any offers. However, if you’re only sharing general information about your standard products, your operating hours and location, then the decision to update the message can be more reliant on metrics.