The 2017 Canadian Computing Olympiad will take place at the University of Waterloo on May 11 and 12. This is the primary contest used to select Canada's IOI team. Each day consists of 3 problems in 4 hours. Problems were prepared by past CCO/IOI contestants.
For the first time ever, there will be a online mirror hosted on DMOJ after the onsite contest is over. You can find more details on the contest page: Day 1 Day 2. The mirrors will be available starting Midnight EDT May 13, 2017 for 60 hours. You can choose any 4-hour window during the 60 hour window to participate.
Past CCO problems are located on DMOJ. Personally, I think the difficulty will be similar to the past few years.
University of Waterloo offers Mike & Ophelia Lazaridis Olympiad Scholarship, a full cost scholarship for IOI/IMO medalists to study in the Faculty of Mathematics. Generally up to 4 students have received this award each year. Current recipients include FatalEagle, zxqfl and students from other countries. Note that funding is running short now, so 2018 may be the last year this is offered. If you are interested feel free to message me or reach out in person to Troy Vasiga, the Canadian Team Leader at IOI 2017.
UPD: Mirror starts soon, good luck.