Hi @Karen Lawton
Thank you for reaching out to Microsoft Q&A forum.
To identify whether if you have Classic or New Outlook, you can look at the icons. On the left will be Classic and the other one is New Outlook.
For your feature request, I honestly understand how convenience this feature would be for you and your colleagues. I'm sure it will save time for your workflow.
Unfortunately, this feature is currently unavailable. However, I do find these feedback that have the same feature request as yours.
Change hour delay delivery · Community
Customizing Default Time of Delayed Delivery of Emails · Community
My recommendation is to upvote for these ideas, the more people vote for it, the higher chance Microsoft will make this a feature in the future.
Microsoft will listen and try their best to enhance customers' experience.
I hope this information is helpful to you.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
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