Mine tend towards the latter for both internal and external and only get a little more expository if it’s a closedown period and I’m adding leave to one end of it, but that’s a simple “The organisation is shut between X and Y. For emergencies during this time please contact Team. I am on leave between Z and B and will not be accessing my email during this time. Please contact Email Address if your enquiry is urgent otherwise I will attend to your email as soon as is practicable upon my return.”
When the office remains closed for any holiday, the messages informing the employees about the holidays and wishing them on the holidays are sent through cards or text messages to the staff. One can also send the wishes through mails to all the office staff.

I, for one, tend to forget to set my automated out-of-office (OOO) email responder and scramble to do it before the plane takes off 🙈 It’s important to inform your customers and business associates (and remind your colleagues!) that you’re away, especially if they’re expecting a prompt response.
Manage your customer's expectation by setting up eDesk to auto-respond to any messages that arrive when your offices are closed for a holiday. This help file will guide you through creating Out-Of-Office templates that will be sent automatically to customers during one-off office closures, such as during holiday periods. Before you start You’ll need to have access to Templates in your Settings in order to view, create and edit templates. If you don’t have access, you can request it from an Admin user within your business. Note: To find out about the other types of templates that eDesk supports, click here.