Supertwinfan’s answer is not entirely correct. PGC takes only the top level data (= country) from geocaching.com (and thus from the CO, who, unfortunately, can also assign the cache to the wrong country).
However, second (= state) and third level (=county) luckily are NOT taken over from geocaching.com but are calculated autonomously, mainly based on OSM. So, the first step to have correct assignments is to have correct boundaries in OSM, but as the change took place in 2016 I trust this has been taken care of (I just checked, indeed that’s the case).
Secondly, PGC has to update the polygon data. This is not an automatic process but needs manual input, and I understand that it is quite tedious. However, of course such changes to provinces as mentioned by the TO would warrant an update, and I assume that the wonderful people of PGC will take care of this as a result of this thread.
