Unexpected Command Ship Behavior

I am playing as the Torians and I assigned a leader to the "Tlas's Flagship" command ship.  I used that ship to attack a Ship Graveyard and it successfully killed all 3 defenders.  However, I noticed that the ship gained 6 hit points after the battle, which was unexpected.

The first screen snapshot below is from the Battle Report and it shows that the ship's hit points are 77 out of a max. of 80.  The second screen snapshot was taken after exiting the Battle Report and looking at the ship's data.  Notice that the ship's hit points are now 77 out of a max. of 86.  The "Special Abilities" for the ship say that the ship gives 5 influence to every world after each battle.  It does not say anything about adding hit points.

I am not complaining about getting free hit points, but I thought the programmers may want to look at this command ship (and all the others) to make sure it does what it says it should, no more and no less.