Interestingly, the Keystone manual says in the US, the CCC weight on the trailer sticker is with water tanks dry. Whereas a Canadian rig, the CCC weight listed on the trailer sticker is with the water tanks full. It is not clear, but appears the Canadian sticker number is lower to reflect that water weight than the US sticker with no water included.
See pages 22 and 23 of the manual.
https://keystone-rv-dealer-app.cdn.p...al_revised.pdf