My "Bungle Wasteland" science museum is "16 years old" (in game time). The museum's two ready-made helipads (one museum-style and one Bungle-style) became non-interactable overnight (in real time). I had enough money to add a third helipad today, and that new one is interactable. I tried restarting my computer. I recorded a video clip showing attempts to interact with the two old helipads (and failing) then interacting with the new helipad (and succeeding).