I am more of a musician than a dancer, so if you want to look at it in terms of the music than the steps this might help.
In East Coast, dancing 6-count sequences will give 1 and a half bars of 4/4.
If you dance, then, 2 basic steps in EC you get a total of 12 counts (or 3 bars of 4/4). It then is resolved at the end of a bar.
If you are thinking in terms of staying even with other 8-count dances (eg Lindy Hop):
Three sequences of LH are 6 bars of 4/4.
Four sequences of EC are also 6 bars of 4/4.
So in reality the dance will not get ahead of the music (although it sometimes feels that way)it actually falls behind, and just takes one extra sequence to catch up. East Coast is syncopated to an extent if you look at it that way, but that can add to the enjoyment of the dance.