From the other thread:
Ship just after Privateer promotion.
It does not work.
Nothing is updated, neither the info nor the icon of the ship.
Privateer promotion is pretty special. So something like an admiral promotes like this:
Blueprint is found in CommanderStaticBlueprintDefs.
But a privateer promotes like this:
On the screenshot, it's turn 151, you have no snuggler colony. Are there any pirates on the map? Are you doing something wonky for generating the commander or promoting?
When promoted, privateer instantly changes model if zoomed in, or icon if zoomed out. The lower left window info updates once you un-select and select it again.
That being said, privateer seems completely detached from your own research. If you have no militarization tech, apart from War Machine so you can upgrade the commander, privateer you get is a "Battleship M0" (escort, large hull, 5 superior railguns, 2 hull platings, hyper drive, life support). This seems to be base privateer model, or base pirate best ship. You can get this on turn 2 (using console to get resources and finish research, and being exterminator for free commander).
Next design in the line replaces 5 superior railguns with 2 superior railguns, 3 basic railguns and a kinetic accelerator.
I have gotten carriers from the upgrade as well, destroyer-l(missile oriented ship) and so on.
As to when designs update and what ship you get, seems very random? Before age of war, it seems it's always that first design you get, but when do pirates update their designs, how do they research...it's very annoying not knowing what you get or when does it change.