Weird co-ordinates
 

Since I updated to the latest (unstable) patch, co-ordinates given by HQ don't appear as normal latitude and longitude. They are given in a way that I don't understand, e.g. 673S 347W. That doesn't even appear to match the U-boat grid system. It is further compounded by the fact that neither latitude nor longitude appear on the maps. Perhaps there is an easy explanation, I would be grateful if anyone can shed some light on this for a simple old codger.