Supposedly flying home after an excellent holiday in North America we instead sat in Toronto Airport for over 12 hours. On arrival we discovered the flight had been delayed by 6 hours because of a mechanical issue. In the end we were left in an empty airport until after 04.00 in the morning, departing many hours after the 'supposed' Help Desk had gone home. We received little information and no support, though we eventually, after much queuing, were given some free food. At one point two flights to Heathrow were called to the same gate and they then boarded the passengers who were due to fly 4 hours after us. We were offered no compensation.