How often is the ITN Layer updated?
It is updated when changes occurs to the Ordnance Survey large scale topographic data, information from DfT, Highways Agency, Highway Authorities and our own field surveyors. The aim is to include information in the OS MasterMap Topographic layer within 6 months of change occurring, ITN layer information, taken from the topographic layer, will be updated shortly after its publication in the topographic layer. A refresh is available to customers 6 weekly.
