Construction priority ignored

With various items set with priorities, trucks are still building items with priority 8 before items with lower number (higher priority).

Update 4, v0.8.2a (b552)

I am having this issue as well. It is causing maintenance to die off because the trucks are not delivering materials to be turned into maintenance. It is set to priority 1, but they are doing stuff that is set to 8 or even lower. I am looking at materials in my unit storage that trucks are just refusing to take over.