There are some object categories in OSM whose exact classification is often a matter of contention and edit wars. Main highways are one of the most prominent examples. There was a small edit war in Poland which resulted in no less than 4 blocks, but I did not let that crisis go to waste:
Behold road-watcher, a quick Python project that regurarly queries Overpass API for highway=secondary and above within a specified boundary and then detects any classification changes, sending them to a Discord channel (though it’s trivial to substitute it with another means of notification).