Yes, it's all very confusing!
At the start, Nasty Nancy has long, straight dark hair, and wears a light-coloured top - her breasts are quite small. Later, she has lighter-coloured curly hair, and wears a black bikini, like Double D - and her breasts are larger -similar to Double D. Either it's bad "continuity". or the orginal "Nancy" was injured.
Also, at the start, Double D was not wearing gloves - but later she was wearing long gloves like Nancy. But it looks like the "original" Double D still.
I'm now even more confused now - think I'll not do any more delving!