Before I set out for a ride today my Edge 830 decided to apply a firmware update (probably irrelevant to my issue).
Whilst out riding the weather turned and I decided to get the device to route me home.
During the ride I not only noticed that it told me to take the first exit on a roundabout that was correctly drawn on the map showing I had to take the second exit but it also showed that I show travel anticlockwise.
I don't use navigation very often but given todays discoveries I will be exercising caution on the occasions I do.