Sunrise and sunset time can be very different from one location to another, even within the same timezone.

I have devices at multiple locations, in different US states.

Location could be picked up automatically from device/router IP address (geolocation) or should be allowed to be chosen manually or synced with GPS at setup time. User usually needs to be in proximity of device when setting it up but can be far away when controlling the device.

Alternatively, groups of devices should allow different locations, e.g. "Summer home in Vermont" and "Winter home in Arizona" (different sunrise/sunset/timezones between the two).