Is the maintenance regime for OS MasterMap Topography Layer the same as for Land-Line?
OS MasterMap Topography Layer is created from a master dataset which is refreshed regularly (every 6 weeks). The Topography Layer works on the principle that you will take an initial supply of all data in your area of interest and then update the data by taking change only update (COU). COU brings your database up to date with the most recent OS MasterMap data available from Ordnance Survey. The COU will contain only the features that are new or have changed, as well as departed features (information on features that have been moved or deleted). Any feature that is new or has changed since the COU date you specify will be supplied with its latest version and ‘departed features’ will indicate which features have been moved out of your area of interest or deleted since that date.
