Yes, I am differentiating between the two, and focusing on the former.
As I understand, many gentlemen volunteers were short on cash but nonetheless hailed from elite or middle-class families and had the *manners* and education of gentlemen, as evidenced by their messing with the officers even before being commissioned. This is distinct from ranker-officers who did not have the manners and education of gentlemen before being commissioned. There was considerable debate over whether promoting men from the ranks was a good idea – with a general consensus that some such promotions for exceptional merit were permissible, but that too many plebeian officers would endanger mess-room social harmony and homogeneity.