So the shop just updated at 12 noon PT, on the last week of daylight saving, 2 hours after the normal shop reset time during DST, and 1 hour after challenge reset.
Even as a programmer myself, I can't fathom what kind of twisted spaghetti code would result in this. The only way I can understand this is if they simply forgot to create a shop rotation for the last week of the season, and had to manually update the shop after they realized their mistake.
Also, Khaki Runway contains the same coating for the same vehicle twice.