Confused about Resurrection

There is quite a few posts on that topic, but in short it seems to be that resurection takes the highest level of Your capital ships lost, no matter where it was destroyed. So did you lose a level 6 cap ship anywhere?

Basically, if you lose a level 6 radiance, you can target a new level 1 radiance to immediately upgrade it to level 6.  This is quite nifty, as so long as you have ressurrection you never actually lose experience progress on your capital ships.  Of course, this makes it less useful for your first capital ship and more useful later in the game once you have multiple higher level caps.

What I don't get about it is if you target it against enemy ships or friendly ships that recently got destroyed? And whenever I turn it to autocast it just fires off whenever the cooldown is ready, no matter what my fleets are actually doing.

The tooltip could be better.

it seems the ability actually keeps track of ressurections available, I.e., one destroyed level 10 halcyon can't get you 15 level 10 halcyons(pity) only works for YOU not your allies or your enemies.

The auto-cast is broken; it just randomly targets any nearby capital ship whether or not the ability will actually do anything.  Don't use auto-cast with this ability.  In fact, there are almost no ultimate abilities you would ever want to set to autocast.

But how are we supposed to use it in the first place? Do I have to wait until a ship actually dies in combat before targetting the wreckage and another cap ship of a lower level?

ressurection automatically knows all destroyed cap ships of yours. you just have to target it on the ship you want to inherit the levels