In the barbarians, I have upgraded a couple of mines when they ran out of coal, but I do not have enough Chief Miners to get one of them going.
My scenario: I have built several coal mines on a mountain. Some of them start reporting that they are out coal. Without coal to dig, my miner is not going to get more experience. One of the mines has a Chief Miner, but the other has only a Miner. I upgrade each. When the first Deep Mine is ready, the Chief Miner, and the Miner from the still upgrading mine come out and occupy the first mine and everything is fine. When the second mine is finished, a new Miner is created and occupies the second Deep Mine. This new mine reports that it is missing a worker. It appears that this mine is totally inactive without a Chief Miner working in there as well, but I do not have any more Chief Miners.
A little while later, I notice that the first Deep Mine now has two Chief Miners, as my Miner has received the experience and is now a Chief. So now I have two Chief Miners in one Deep Mine.
I want to kick out one of the Chiefs to go work in the other Deep Mine and get a new novice in the first Deep Mine instead. Is there a mechanism to do this and I just missed it, or this is accomplished using another mechanism or would this be a new feature request (let me select a worker and kick them out of the building to go to another building that is requesting that type of worker)?