Quoted from teekee:
I am no expert but looks to me like they assembled some playfields before all the layers of clear were cured.
Guy who works in the clearcoat industry was on the TWIP podcast today. He said any properly mixed clearcoat should be cured enough after 7 days to "return to service." In his opinion, any clear that is still malleable weeks or months later didn't have enough hardener in the mix and will never stiffen up. In other words, it's as cured as it's gonna get. That's just one professional's conjecture from seeing photos, but it makes sense to me.