Thanks for your reply.
I have flight another drones with Naza and other FC, with the function to show the home point in the FPV image. But in this case, the "H" symbol didn't correspond to any 'logical' position of the home point.
According with your explanations, when the drones approaches to the real homepoint... the "H" symbol would be showed behind the arrow, but this did not happen.
Even when I was flying in stationary exactly above the takeoff place, the "H" symbol appeared to one side of the arrow.
(sorry for my poor english)