Set the days during which your holiday auto attendant operates. You can assign a holiday schedule created previously, or create your own holiday schedule for the auto attendant.
These are just a few ideas to get the gears turning. These are simple examples, but don’t be afraid to show a little personality.

If they are calling without an expectation that you always pick up (such as if you are a business coach or a one-man shop) then thanking them for calling might make the most sense.
To provide as much helpful insight to businesses as possible, we've compiled the top must-have information that should be included in your office's temporary voicemail greeting. 1. Your voicemail should be timely and relevant to the situation at hand. 2. Indicate if you’re working remotely or changing office hours temporarily. 3. Set clear, reasonable expectations for your callers about when they should expect to hear back from someone. 4. State clearly what types of matters are urgent and give examples of issues that are not. This way, patients and callers can have a good understanding of what to expect about call-backs and reduce unnecessary follow-up calls. 5. If you have made disruptions to existing appointments, you should note this, as well as how you plan to reach people to reschedule.