My OOO is almost always “I’m out of the office and will be returning on x date.” My email sig has instructions along the lines of “for questions on x, email this list” for a couple of the more common areas people would contact me about that might need an urgent reply (as the lists go to more than just me, obviously), but most people have finally figured out to contact those lists to start with, anyway. If I were in the middle of a project or something that needed to be moved along in my absence, the project teams usually know when we’re out, but I’d put a back up in that case, if needed, but generally there’s not much to be gained by a longer OOO from me.
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Thanks for your message. I am out of the office today and have limited access to email. If you need immediate assistance, please contact [Name] at [phone number], or you can try me on my cell phone at [phone number].
That’s what I always reasoned… better to annoy with too much information that saves hassle on the backend then be brief upfront and sentence people to OoO purgatory.