Mary founded Instructional Solutions in 1998, and is an internationally recognized business writing trainer and executive writing coach with two decades of experience helping thousands of individuals and businesses master the strategic skill of business writing. She excels at designing customized business writing training programs to maximize productivity, advance business objectives, and convey complex information. She holds a B.A. in English from the University of Rhode Island, an M.A. in English Literature from Boston College, and a C.A.G.S. in Composition and Rhetoric from the University of New Hampshire.
Thank you for your email. I am out of the office in observance of [holiday] with limited access to email and will return on [date]. Your message is very important to me, and I will respond as soon as possible. If you need immediate access, please contact [number].

An out-of-office message is an effective way to inform people why you are not responding to their calls or messages and when they can expect a response. This information saves them from getting frustrated and avoids any negative impression from the inability to respond. If you have long-term relationships with your customers, such an auto-response system is highly significant as it avoids any inconvenience.
I thought it was cute and could tell that the person writing it probably spent a lot of time on the road and needed a shorthand for updating their message.