4. Vacation Day Voicemail Greeting. If your business is off for a holiday, it's a common courtesy to update your voicemail to acknowledge the closure. Mention the closure in the beginning of the message, convey when your business is reopening, and don't forget to wish the callers a happy holiday if the occasion calls for it.
Website: https://shoretelcommunity.force.com/s/article/How-to-Record-and-Change-Your-Voicemail-Greeting

As you can see by reading our article on how to write the best voicemail greetings, they’re a bit more complex than one might imagine. There are important elements that cannot be left out, as to do so could cost you valuable business contacts. We realize this, so have included a selection of more funny, professional, and personal greeting examples, in MS Word and PDF format. By using these voicemail greetings, you’ll be well on your way to craft a greeting that will be pleasant to hear, provide the correct information, as well as requesting the correct information.
Some people try to get really fancy with their voice mail greetings and they will put the current date on their message. This requires you to update your voice mail greeting daily. This level of customization is completely unnecessary and often leads to problems when the user forgets to update the actual date itself. However, updating your outgoing voice mail message to reflect a particular season or holiday can be a nice touch as long as you remember to change it accordingly.