How the Military FF Promotions work?

[Cort Haus]

Which units benefit from the promotions of some of the Military Founding Fathers? Do they apply automatically but to only veteran troops? Do they apply to existing vets, new ones, or both?

[Sir Alkis]

The units that get the benefit are listed. Gunpoweder units means your soldiers. Dragoons are mounted units.

The bonuses apply automatically and not only to veteran troops.