No clue, but since this is a card of accomplishment maybe it's using what she has learned, perfected and worked hard for in the three of pentacles and the 6 Pentacles is the fair trade recieved for her efforts. Getting out of it, what she's put into it.
It could be that 6 is the number of nurturing and protection, and 3 is the number of sociable creativity (among other things). The isolated lady seems to prefer to keep her hawk hooded, and would shriek to notice the slithering slug in her perfect world. I do love this card, but it always makes me think...