Our home security system is usually in the same mode as yours all are, but she went on high alert last night at 3:45 from her crate in the kitchen. Usually it is just a stray cat or raccoon bumping around the empty cat dishes outside on the deck so I didn't jump out of bed. When that is the cause she usually quiets down after about 5 seconds, cause they make a run for it since her crate is on the opposite side of the sliding door glass where the dishes are.
She kept at it for about 30 seconds, and I slowly rolled over to look out the window thinking we just had a remedial raccoon that was slow to leave. The outside lights go off at 3 so it was fairly dark, but I swear I saw the shadow of somebody run past the one car in the driveway. That got my attention and out of bed and out the door in a hurry. When I got outside and down to the driveway I could see taillights about 500 yards down the road. Problem was the keys that are 99% of the time in my pants pocket were on the counter and I had to run back in and get them. By that time, they were gone, although I still drove up and down the road a couple times to see if I came across anyone, but no luck.
Nothing was missing from the car which was unlocked and has the usual handful of change in the cup holders and ashtray.
I will be changing the timer on the outside lights to stay on all night and locking the car and garage doors. And the security system gets some extra belly scratching.