This advanced setting in the Supermetrics for Facebook Ads connector Determines the report time of action stats (aka conversions).
The setting has two available options:
- On conversion date (this is the default)
- On impression date
This setting will change the behavior of how conversions are counted, based on the user impression or actual conversion event dates. For example, if a person saw the ad on Jan 1st but converted on Jan 2nd, when you query with the setting "On impression date", you see a conversion on Jan 1st. If you instead use "On conversion date", you see a conversion on Jan 2nd.
Do be aware that as of April 26th, the Facebook Ad Manager UI now defaults to "on conversion date" for its calculations, so changing this setting in your queries could lead to false discrepancies if you are not careful.