Yeah, announcing you were going to delete emails unread and expecting the sender to resend when you return would NEVER fly in my office. I’d get executive complaints about that, especially if it went to a client or outside party – if a client can’t reach you, they will reach out to someone else who may not work at your organization and you lose business. I feel like this delete-it-all philosophy would only work for an entirely internal role where timelines are more relaxed, and even then, I feel it’s a bit unprofessional to foist your own catch-up work onto others, especially if they’ve been backfilling for you while you were OOO.
Of course he presumably meant working on a trial – yay for regional preposition differences!

Write a short, direct subject line.State your purpose for writing.Include the dates you're requesting.Consider mentioning why you're taking time off.Discuss how you're preparing for time off.Remain available for questions.
If you’re feeling stuck, try our free OOO email generator to draft a message that perfectly captures who you are and where you’re going. Out-of-Office Messages for Vacation 1. “I’ll email you back once I’ve defrosted.”