It is now possible to select which attribution window you see for your conversions with only a few clicks. This allows you to easily adapt the attribution to match the settings of other channels you might be optimizing or reporting from - e.g. Google Analytics, or to simply unify the attribution settings across different campaigns that might have different attribution settings in Facebook.
Account uses the Attribution Window setting specified at Ad Account level.
Unified uses the Attribution Window setting specified at Ad Set level. If the Ad Sets have different settings then no data will be shown.
Manual forces the specified Click Days and View Days to be used.