We filter on null values in almost all of our reports, power lists, and rules. In these cases, when I need to include a null value I select the field, select the "equals" operator, then check the box (it now has the wonderful help feature that explains what it includes or excludes, see below screenshot)
The other day I created an outreach that had several variants with filters on null values. I set up the variant filters that needed to include null values the same way I would set up the report, rule, and power list filters. The screenshot below shows how I set that up.
However, when I checked to make sure everything was running correctly, [i]I noticed that the emails were backwards. Those clients who should be receiving the variant with a null value were receiving the email that didn't have a null value and vice versa. When I flipped the operator from "equals" to "not equals", everything started working as needed.
Has anyone else noticed this?