It happens that a flight is overbooked due to different reasons, such as change in aircraft, demand for more fuel due to weather conditions, resulting in fewer seats, or irregularities.
There can be 2 outcomes for the passenger:
The passenger can be denied boarding due to the overbooking and in case the passenger does not voluntarily stand down, the passenger has the right to be compensated, incl. accommodation and food if needed.
There will be no compensation of the passenger if rebooked within 4 hours.
It is possible to cancel and refund the ticket in case the purpose of the trip is forfeited due to denied boarding and the passenger chooses not to be rebooked to a later flight.
If the passenger accepts the rebooking, the passenger will be rebooked to the first available flight or to a later date, chosen by the passenger.
There can be different rates of compensation, depending on where the passenger is flying out of.
To see the amounts, please see the applicable rules here: http://www.airgreenland.com/media/507815/110617_GRL_Irregularietsfolder_UK_web.pdf
In case the economy class has been overbooked, but seats are available in business class, the passenger can be upgraded at no extra charge.
The passenger will keep the 20kg in baggage allowance.