Temporarily connect a clock to the circuit, set it to correct time, and you can see exactly when it trips.
Super genius!!
Not sure I have a mechanical clock lying around anymore, but I love the cheap troubleshooting idea.
Other quick ideas...
Depending on how the PC works and your access to it, you might be able to shade the sensor (or put a bag over it) and get the lights to come on. Then you can test current draw, FOP across breaker (and PC).
And most importantly, then you can remove the shade or bag, the PC should turn the lights off and you can be right there to observe what happens.
Just thinking out loud.
Will also echo the check of the PC rating for LEDs. But, the big problem typically with LEDs is current spike at switch ON. I've been meaning to create a thread on this with some interesting problems I had 2 years ago with switching on some LEDs and the problems it caused on a custom made system we were building. That's not to say bad things could happen at switch OFF.