Let me add a couple things I have noticed about this, this might help in re-producing the bug.
If you are producing a building and add a unit to the que, then switch the unit to the front of the que that unit will have whatever the cost of the building would of been to finish. As long as you do not back out of the que. This does not work for buildings however, you can be producing a building and move another forward, the cost will not update, until you move out of the city view, but it will not rush the building; unless you have its correct cost.
