Question, Is 9:59 significant to you? Or are you using that number as always beyond sunset?
I used to use sunrise and sunset but was never happy. Now I use an Hue outdoor motion sensor which has a luminence sensor built in. After a little trial and error I've dialed it into the amount of light that I do not want my lights on. At that point simple light automation works beautifully.
Additionally I have it in my garage next to the window to see as much light as possible, but the real treat here is unlike most motion sensors this one isn't affected by temperature. So now I have dependable motion sensing in the garage.
Should be noted in my setup it does not really track outdoor luminence as a scientifically relevant number as it is in my garage, but that's where the trial and error comes in. Couple sunrises, sunsets, and overcast/rainy days and you will have your baseline to build your restrictions for your automations. It's economical because that one sensor handles all my luminence needs.
One thing I haven't dealt with yet is when the garage lights are on in the night, but I'm rarely it there, guess I could throw in a restriction based on the garage lights status.