Two weeks after the first they added a second screwdriver line above the first. At least I know it was someone who either knows me or my car. I hope they do it again so I can pinpoint the time and place.
My advice to you. For the next month check out your car every time you go back to it if you park outside of your house garage. That way you can see if someone has damaged it again - that way you can eliminate time and places.