I used to work with someone who had a message telling people she only checked her email twice a day. You pretty much needed to call her if you needed anything outside of those times. (She worked in a remote office.) I think she had read one of those books on efficiency that recommended scheduled email time. But there were problems with this: 4. My department often had to email attachments or text to illustrate our questions/concerns. And we were on deadlines. Reading a page of text over the phone was not an efficient use of anyone’s time 5. She did outreach & was often out of the office on site visits, trainings, or travel to these places, but never ever set her OOO for these, because she was “working.” However, she was effectively not available to read emails from other staff until after hours on those days.
Thank you for your email. I am no longer with [company name]. Please direct enquiries to [insert name and email] or [insert name and email].

I’d just stick with “I will be OOO without access to phone or email from XX/YY to XX/YY, returning on XX/YY.” And then whatever directions for directing to your support/backup while you are out. I find that specifically saying ‘without access to phone or email’ sets a good expectation of non-response.
Ann Handley is one of the renowned digital marketers who is also known for her sense of humor. In the below auto-response, she has sprinkled some clever creativity, personalization, and warmth instead of the two-line cold replies that we see almost everywhere. This can surely be an inspiration for anyone willing to catch the reader’s attention and make them smile even while away.