What behavior is expected when the "Overwrite Prospect Opted Out field" Salesforce connector setting is...

Only users with an Administrator user role will be able to change the prospect field value.

The record that was last updated sets the field value for a synced prospect.

Only 200 records per day can be updated to overwrite the "Opted Out" field value.

Opting out a prospect in Salesforce or Marketing Cloud Account Engagement deselects the "Do Not Email" field upon sync.