The Pending Points cockpit setting makes it so that a guest's points lag behind for a time (one hour, for example) before they are added to the guest's total. This will allow the system to account for any adjustments made to the receipt, ensuring that your guests earn the correct amount of points and are not awarded for items they didn't purchase.
When this setting is turned on, future test barcode checkin will not be recognized. As such, this is not an applicable way to test Pending Checkins.