Jeff_
1 did you pay Sale or Presale prices for your tickets? If the sale prices were used then it is proven that the sale was on and it was 9th. January!
2 Was the origin of origin of your flights CDG or another airport in the same timezone? If it was a timezone Westwards say LHR and you made your booking before 01.00 CET 9th January then date at flight origin was still the 8 th January.
I am not looking at the right or wrong of QRs action just at probable causes. I am sure there are others that we know nothing about.