they are moving away from fall-spring shots to 1 vs 2 shots per year because of the timing of surges, the way the vaccine works/wanes, and economic modeling on cost of vaccine programs.
certain populations seem to be more cost effective to vaccinate twice per year, or even more than that, with at least 3 months between shots
other populations, pretty much anyone over 6 months of age, appear to be more cost effective to vaccinate once a year
the issue, of course, is the vaccines aren’t perfect at stopping illness, there is low uptake, and they can’t fully calculate the cost of not getting vaccinated, so outside of populations that are at a higher risk of complication it’s hard to do the cost-based analysis.
BS, poor reporting or bad faith reporting, you can read the actual recommendations here: https://www.canada.ca/en/public-health/services/publications/vaccines-immunization/national-advisory-committee-immunization-statement-guidance-covid-19-vaccines-2025-summer-2026.html
In summary: