There ought to be a word - and perhaps there is, in German - for the mix of feelings that accompanies composing and activating a holiday out-of-office message. There's smugness, of course, and a gratifying sense of laying down one's virtual tools after a horribly long shift. But for many of us, these nice feelings are tempered by the knowledge that in two weeks, refreshed but depressed, we will have to trawl through hundreds of emails, many of which will be conference room notifications for meetings about crises that have passed.
As long as you’ve covered the basics—dates of your absence and who to contact in your absence—you should be good to go.

I have a coworker that purposely leaves them on the first day that she’s back in the office (even though it said she would be back today) because she thinks it signals that she’s still unavailable (while she needs some time to catch up.) I think it’s a bit confusing. I personally would feel weird doing it because it seems like I just never came back from vacation.
Here's an auto-reply I created for my support account having some fun. But also throwing out an extra lifeline on the off chance I'm eaten by a bear. If the boss doesn't notice I'm missing, surely people emailing me will, right?