I noticed yesterday on a long motorway trip that the satnav often thought I was turning off the slip road and showed me tracking to the left along the slip road although I was still on the main carriageway. The correct plot was shown as soon as my true position was more than about 30 yards from the wrong estimated position on the slip road. It almost seemed that the satnav was incorrectly estimating my position some yards to the left. Has anyone else noticed this behaviour? PS I have the UK spec satnav and I'm using maps from Dec 2016.