I worked for a federal contractor back during the Great Recession when government offices were shut down/working with a skeleton crew. I still remember getting OOOs from almost every email address in the agency we worked at explaining they were on furlough & to contact one specific person if the issue was urgent. We all assumed this poor person was hiding under her desk, rocking back & forth, with her head in her hands.
What we need in our work communication is not more professional politeness or less formal, chat-based messaging applications like Slack. We need honesty. The problem is that we’ve conditioned ourselves to see honesty as self-indulgent or disrespectful. I’d argue the opposite is true. Honesty, even if it’s a bit more inconvenient for all parties in the moment, pays dividends later. It builds trust. When my partner Anne Helen Petersen and I were interviewing people for our forthcoming book on remote work, a frequent lament from both middle managers and workers was that they didn’t feel like they knew how to succeed in their jobs; that they were guessing what their superiors and coworkers wanted and, even when they asked, they didn’t quite trust the responses they got back.

I appreciate your email. Currently, I am out of the office but will return after (Date of Return). My access to email will be limited during this period of time.
Happy Holidays and thank you for your email! I’m currently out of the office and will return on [insert date].