I use Ventus Pro to Ping the Start line into Expedition and to the B&G H5000 GFD.  When to boat is stationary the GFD Start Display shows the distance to the start line as 36’, which happens to be the length of the boat and GPS offset distance from the transom to the bow.  If I go into Expedition and remove the GPS offset the GPD displays the correct distance, roughly zero.  

if looks like Expedition offset and the B&G offset, or Ventus offset are being added together.  Should the offset be removed in Expedition or in the B&G setup.