Rules for Entering Class Divisions in a USCF Tournament

This question if for all you USCF TDs and frequent tournament players.

So while I was registering for the US Class Championships this year, I entered into the Class C division because my rating was 1434P and the Class C division showed ratings from 1400 to 1599.  But after the tournament, I noticed that there were three players, going into the tournament, who had a rating higher than 1599 (see note below).

Why could these three players enter a class division from 1400-1599 when they had a rating higher than 1599?

Note: the three players had ratings of 1639, 1690 & 1702, so a couple of players were around 100 points higher than the upper limit of the Class C.