In the instance that a driver notices an incorrect sign-posted speed in SmartNav: Navigation, they can update request request to have the map data updated by sending an email to NextGenSupport@TeletracNavman.com or by using the app on their iFace.
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This report is sent directly to the map provider, Here.com, who will assess the request, based on the location at the time that the Send button is tapped.
Please note that updates are released quarterly so can take a minimum of 6 months to be pushed outsometimes take up to 4 months to become available.