The provider that we buy the IP database from does update the IP addresses monthly.
There are only a small number of GeoIP database companies and all can be slightly hit and miss due to IP changes. For example I tried the link you gave and all the UK IP's I try, including our own IP ranges, it can only give the country and not the city or region, so is less accurate than the GeoIP database that we are using for the IP's that I tried.
If you could send me a PM with the affected IP's with their locations I will refer it to our GeoIP database provider and ask that they look in to updating them.