not A,B,C reps.
when a maker construct a watch, they give to other single part and case manufacturer the order, based on tech drawings or based with the single part or and case to make the tech drawings
to manufacture the parts. sometimes one manufacturer or several manufacturer.
the maker build everything together, but when some parts like crown-guard and lever are not perfect, they use it for B or C-Stock and pricewise cheaper.
hublot comes from a maker, he is watchmaker, he makes only A-Stock, that's why he is always very expensive.
but many of other brands come from the noob factory, so also most of the pams.
the daylight is a partnership project with a factory. believe me, nothing goes in a trash. everything is good for money. that is chinese mentality.
rolli