I worked at a public agency and would have different out-of-office messages for internal and external. I was chastised for having a “too informal” message- because the idiot talking to me didn’t realize me saying “I’ll be back next Tuesday for the big staff meeting” (or whatever) was just for co-workers and not the public. I told them but of course it didn’t matter. So from then on I always made sure to start my internal OOOs- “Hello Company X comrade…. blah.” So it was clear which was which. I am not able to respond to your email promptly because my husband died. I will not be accepting zoom invitations. Please do not respond by suggesting future alternative dates. I don’t know when I will be able to speak without crying.
This is how my voicemails to my doctor’s office, my son’s doctor’s office, his daycare, etc. all go. Actually, the few times I leave voicemails beyond that, this is how they go.

Remember, your email signature is as important to your company as all of your other corporate branding. Update any marketing promotional banners with seasonal offers. When the holiday season is over and your promos have finished, make sure you are no longer using a Christmas themed banner.
An out of office message lets you keep people informed and tells them how to proceed in your absence. You can also select options for urgent matters within your out of office message.