I'm not seeing it either if it is being updated, so I get the vibe that there's no scheduled task for updating it.
It's probably a fairly processor-intensive thing, so maybe doing it once a week would be okay? I know the town world map has updated less often than the wilderness world map, but the exact timescale I'm unsure of.
I'd definitely like to see the town world map updated more frequently though, it's always rewarding seeing your hard work come to life.