3. When does/did eTA come into operation?
Since August 1, 2015, eligible travellers have been able to apply for an eTA. Visa-exempt foreign nationals are expected to have an Electronic Travel Authorization (eTA) to fly to or transit through Canada. Exceptions include U.S. citizens, and travellers with a valid Canadian visa. Canadian citizens, including dual citizens, and Canadian permanent residents are not eligible to apply for an eTA.
However, until September 29, 2016, travellers who do not have an eTA can board their flight, as long as they have appropriate travel documents, such as a valid passport. During this time, border services officers can let travellers arriving without an eTA into the country, as long as they meet the other requirements to enter Canada.