This feature was working with my WLED Light bulbs and homemade LED Arches turning on at sunset and off at sunrise. But today I noticed that they didn’t turn on so I checked the Time setup page and noticed that instead of 1558 today it’s showing 00:00. However sunrise is showing correctly.
Reading between the lines on @blazoncek, I’m hearing that the “fast math” algorithm they’ve chosen, doesn’t handle certain cases properly and you’re likely to find “magic” numbers that just don’t work. Changing just up or down from those (by even 0.1) will probably work OK as you found.
Maybe stuck with some of those till a bugfix arrives…