Logically, your formula isn't "counting" but it's dynamically calculating the difference between two dates (aka the duration). You always need to provide two dates in order to calculate a duration.
You have two scenarios:
- Calculate the difference between POC Due Date (a date) and today (a date)
- Calculate the difference between POC Due Date (a date) and "when the approval status field is changed to complete or previously completed" (not a date)
For #1, you have two dates. But for #2, you only have one date.
Behaviorally, you want to "stop counting" "when the approval status field is changed to complete or previously completed", so you need to know the date on which to stop counting. Therefore, you need to record that date in a fourth field.
This is the way.
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gary
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