OG not adusted when boiling duration increases in Recipe Design

A member of BrassageAmateur.com noticed that on the Recipe Design tab,
when increasing the boil duration the OG (after boil) is not updated.
Increasing x 2 results in no change of the gravity.

Hi,
  The OG estimate is not tied to the boil off due to the fact that "Brewhouse/Total efficiency" includes these losses.  The OG estimate is basically a function of final volume, brewhouse efficiency and the ingredients used.

  Also - boiling does not necessarily change the OG if you have the same final batch volume - it does not remove any gravity units.

Brad

Got it, as soon as the final volume won't change I can change the boil duration with no effect.
Of course logically the final volume would decrease but I can do it manually...
Thanks again for your answer.