I have been looking around and I don't see an easy way to do this other than hard coding the dates.
You can get to where you want with 2 filters. Since they both need to be 'true' for the results to show you can use one to find anyone between now and 180 days out and the other for after 90 days from now.
Opened email is ANY
Date of Activity in past 180 days
Not Opened email is ANY
Date of Activity in past 90 days
Does that get you where you need to go?
I appreciate the response, very helpful!
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