I stopped by to see the guys at my ex- work. One guy told me they noticed the furniture had been moved around, and some metal shavings on the tables. He looked up and saw that the fluorescent tubes had plastic clamps holding them in with sheet metal screws. But he didn’t notice one thing: there LEDs inside the tubes! I looked up and could see the round beads of light running down the center of each tube. I tried to take a picture of the tube but it was too bright and didn’t show the beads of light. But the light shining on the reflector has alternating light and dark spots.
The summer work hours are 4 day, 10 hours, with Fridays off. Apparently the contractor has been coming in on Fridays and installing the LED tubes (we can’t call them fluorescent any more!).