Original sentence: Chiltern's PPM is measured on stricter conditions than its long-distance rivals, such as Virgin Trains, as Chiltern has a 5-minute window for performance while others have a 10-minute window
Edited sentence: This is remarkable because Chiltern's PPM is measured on stricter conditions than its long-distance rivals, such as Virgin Trains, as Chiltern has a 5-minute window for performance while others have a 10-minute window