HomeKit 4h before/after sunset/sunrise. Solar noon

I use this useful time relative to sunset to open (open/close what’s the verb here?) an awning. It is very important referring it to that moment of the day, but it falls really short. It should be more than 4hours, perhaps 10 would cover every situation. And even more natural covering of all would be to have “Solar noon” and hours before/after it. So you can automatise actions referring to the real sun position