Read the passage given below and solve the questions based on it.
Bihar Couriers (BC) sends a person on motorcycle every day to the airport to collect the courier. This person reaches the airport exactly when the plane lands at its scheduled time. One day BC came to know that the flight would be late by 50 minutes. So, the BC person also started from his office 50 minutes later than the usual time. However, the plane landed earlier than was anticipated and thus the airport authorities dispatched the courier through a cyclist to BC. The cyclist meets the BC personnel after
20 minutes and hands over the courier to the motorcyclist. As a result, the BC person reached office 10 minutes earlier than expected. (Assume that everybody travels at their own uniform speeds)
What was the delay in the landing of the plane when compared to the normal schedule?