Incident
at 45NM MONTRÉAL / PIERRE ELLIOTT TRUDEAU INTL QC (CYUL)
A Panorama Fixed Wings Ltd. Pilatus PC-12/45 (PNO782) from Quebec/Jean-Lesage, QC (CYQB) to Montreal/Saint-Hubert, QC (CYHU), descending to 5,000 ft, stopped descending at 5,200 ft due to a traffic alert and collision avoidance system (TCAS) warning. The other aircraft, a Cargair Cessna 172M (C-GGJK) on a VFR flight from Montreal/Saint-Hubert, QC (CYHU) to Montreal/Saint-Hubert, QC (CYHU) at 4,600 ft, switched direction without notice. Information on the aircraft was relayed to PNO782. Separation was maintained.