Cetbang cannons

Are the Cetbang cannons affected by Engineering school shipment? As I dont see there name in the discerption for faster training time. Cetbang cannons are the Indonesia’s revolt unique artillery.

I assume that they don’t. Because other upgrades simply say “Artillery: +10% HP” when they affect all artillery units, while the engineering school has a specific list of units affected. If engineering school was valid for all artillery, it would say so.