The long-standing flight numbers for WestJet between YYZ and SXM of WS 2652/2653 were renumbered to WS 2276/2277 for ALL flights on or after October 31, 2024. It was due to a realignment of flight numbers by WestJet. It has nothing to do with equipment changes. That is a separate issue.
As @jaxon60 points out, the only way to tell if your flight has had an equipment change to economy-class-only former Swoop aircraft is to check your reservation seating to see if your seat or class (Premium vs. Economy) has changed. That change can happen at any time right up to departure, unfortunately.
Air Canada is having similar issues, as are a number of carriers, due to the delay in delivery of planned new Boeing 737 aircraft by Boeing itself.
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