This is an absolute dog's dinner of an OP. It got shot to bits in one post because you don't even understand your own model.
A person with a bigger brain would have thought ... hhhmmmmm ... why is the meridian at 12:55pm? 🤔
Well maybe its because Ottawa is not on the meridian. Ok, We know London is ... let's check London.
Dammit ... London is 12:53pm on the equinox. Ok, why else might it not be at 12pm exactly? ... One might suppose that 23.5 degrees of tilt might be fucking things up a bit. Wait a second ... flat earth doesn't have 23.5 degrees of tilt. If I could show 23.5 degrees of tilt gives me 53 minutes on the equinox using maths ... I wouldn't need to travel to Ottawa with a sundial!

... but you're not that smart. So instead we got the awful OP you delivered and we're all going to leave this thread disappointed.
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