I believe that's 5000 lost, not 6000. Still
The event select enemy units of France and does a count. Probably the last selected unit was a GBR unit, and so the faction selector was updated to be GBR.
SelectFaction = FRA
EvalRgnOwned = $Paris;NOT
SelectSubUnits = Area $Theater_France;$Land;Enemy;
EvalSubUnitCount = >=;300
ChangeVPCount = -5000