You can use @Mariano_Colmenarejo virtual device that has sunrise/sunset, and other time/calendar features.
It is summer time on the Northern Hemisphere, people do not realise sun state changes, as it is really out of their interest by having long hours of sun.
If you did it wrong then anybody else can do it wrong, and at the end it leads to frustration from people who are starting with home automation with SmartThings. (because they think that must be the easiest for their use, and then they realise that a simple sun state is not working…)
What could be done is a custom capability that emits a value at sunrise and another at sunset.
To make it usable with positive and negative offsets, something else would have to be added, perhaps two capabilities with +/- time refence to sunset and sunrise emitted every minute.
It could be a custom capability as minutes to sunset or minutes to su…
I think that he will be adding possibility to schedule daylight savings date