According to Air Canada's latest schedule submission to Cirium Diio, significant changes are planned for summer 2026. The airline will resume flights on June 1—earlier than previously scheduled—and introduce the A321XLR for most of the season instead of the larger A330-300. As a result of this change, flight frequency during peak season will increase from three to five weekly departures. This adjustment raises available round-trip weekly seats by two percent and is expected to enhance Air Canada's market share since it will offer more flights than Air Transat's four-weekly service.

Flight schedules indicate that departures from Montreal (AC928) will operate on Mondays, Tuesdays, Wednesdays, Fridays, and Saturdays at 19:15 local time and arrive in Porto at 07:00+1 after six hours and forty-five minutes. Return flights from Porto (AC929) are scheduled for Tuesdays through Sundays at 12:15 local time with arrival in Montreal at 15:00 after seven hours and forty-five minutes.

As of October 23rd—subject to further changes—Air Canada's planned transatlantic routes utilizing the A321XLR include:

- Montreal-Dublin: Starting May 15 with four weekly flights until replaced by a Boeing 787-9.

- Montreal-Toulouse: Also starting May 15 with up to daily frequencies; other widebodies may operate during winter.

- Montreal-Porto: Beginning June 1 with four or five weekly flights replacing the previous widebody operation.

- Montreal-Palma de Mallorca: Launching June 17 as a new market with four weekly services.

- Montreal-Edinburgh: Commencing June 18 with four weekly services replacing last year's use of a Boeing 737 MAX.

On the Edinburgh route specifically, Air Canada launched operations on June 26, 2025 using a three-weekly schedule on its Boeing 737 MAX. According to data from the UK Civil Aviation Authority covering June through August that year, there were about 7,626 round-trip passengers, resulting in an average load factor of seventy-eight percent. For summer season beginning June 18th 2026—with deployment of higher-capacity A321XLRs—the number of round-trip seats offered is set to rise by fifty-eight percent compared to full-year figures for 2025.

The introduction of long-range narrowbody aircraft like the Airbus A321XLR allows airlines such as Air Canada greater flexibility when matching capacity with demand across different seasons or opening new markets where larger widebodies would not be economically viable.

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