Upvote:1
Bookits responsibility was to inform you in a timely fashion of changes to the flight. No question about that.
http://bookit.com/terms-of-use/
It does appear the airline notified bookit, which notified you with ample time to make changes required or cancel your flight however allegedly you were notified with wrong details (the details of which are in dispute).It is a question of whether you were properly notified. From the look of things, your greatest chance of success might be dealing with the airline because bookit.com appear to have fulfilled their obligation of transmitting the notification from the airline to you. If you were improperly notified, then three hours time change in time, especially moving it earlier will be material by most legal standards to claim compensation.
You may also pursue a claim against Bookit.com and/or try dealing directly with the airline.
You can also go through the CTA. The Canadian Transportation Agency, backed by the terms of the Canada Transportation Act, makes sure that carriers fully respect the rights of air travellers and that they keep their promises.
https://travel.gc.ca/air/air-passenger-rights
It offers informal dispute resolution processes, and It offers a court-like complaint process for passengers who want to challenge a carrierβs policies (tariff provisions) as being unclear, unreasonable or discriminatory, for such things as compensation when they are denied boarding or are not adequately informed of changes in flight schedules.
Upvote:2
I'll be a little more realistic in my assessment.
You were notified of a change and the details would be easily available aircanada.com. What bookit.com showed you is easily disputed.
Your likely best outcome is a complaint directly to Air Canada resulting in some bonus miles deposited in your sister's account.