I suspect that the seasons are hardcoded to go: Summer-Winter-Summer-Winter.... regardless of how many turns per year there are.

Since the aging happens in winter, it is not possible to change the rate of aging to true 1 year aged/1 year played, other than by choosing 0.5 timescale. If I am wrong, please tell me what is the other option?

I mean, even if you would get 4 turns/year, would it still not result in aging 2 times per year (once per winter)?