R.G. If you steer on your offset circuit @ 1815 GMT (sunrise o/b was @ 175453 , @ 1815 supposedly 100 mls out , alt.1,000) , the offset lane being 102 mls , you reach the Turn Off Point on the position line @ 1859 GMT , then 30 mls offset to go course 157T and you arrive @ the Howland (assumed) coordinates at 1912 GMT , A/c´s groundspeed 139-140 mph.