It is fascinating tbh. Moreover, it’s currently (as of writing) at 42%. Considering 13:30 is hardly “off-peak”, I’d say that’s pretty damn impressive.

So yeah, going 100% air-source heat pump if you’re area regularly spends time around -30°C (-22F) might not be the best idea. Though even the last report you cited said it might be 1.5-2x as efficient as resistive heating. And that Site 1 with bad COPs was because they manually lowered the fan speed…