Hi @Kim Fowler
Welcome to our forum!
Unfortunately, New Outlook does not support modifying the waiting days for deleted items.
Please kindly understand that many functions are not designed at present. At present, what I can do for you is to submit feedback for your request and I have post here, and you could vote for it. If you have any suggestions or ideas, it's suggested that you could post here.
Feedback: https://feedbackportal.microsoft.com/feedback/idea/a4a0fb2f-15e5-ef11-b542-0022484ce599
Hope Microsoft will notice this in the future. Thank you for your understanding and support!
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