In the instance that a driver notices an incorrect sign-posted speed in SmartNav, they can update request using the app on their iFace.
From the navigation screen:
Tap this button 
Tap "Map error":
And report the speed limit error
This report is If a driver notices that a signposted speed is incorrectly displayed in SmartNav: Navigation, there are two ways to request for it to be updated.
1. Email NextGenSupport@TeletracNavman.com with the following information:
- GPS location or link to google maps
- Road/street name
- Incorrect/correct speed
- Is this a variable speed zone? Y or N (ie. School zone)
2. Report via the iFace
From the navigation screen, tap the button down the bottom right corner
Tap Wrong speed limit
Tap Send
This report is then sent directly to the map provider, Here.com, who will assess the request .Please note that updates can take a minimum of 6 months to be pushed out. based on the location at the time that the Send button is tapped.
Updates are released quarterly from the map provider, and require manual updating over WiFi. Click here for instructions on how to update your device(s).