The Ordnance Survey supply us with map updates on a regular schedule.
Quarterly
1:25,000 scale Explorer
1:50,000 scale Landranger
1:10,000 scale OS Vector Map Local
Half-yearly
1:50,000 scale GroundRanger
1:10,000 scale OS Open Map Local
Yearly
1:250,000 scale OS Road Map
1:1,000,000 scale OS Overview Map