The water will absorb TOC from the container which will not have a measurable impact on conductivity but does count as degradation. When you dispense the water into the jug it will immediately start to absorb CO2 from the atmosphere causing an increase in conductivity and a decrease in pH. Even if you are quick it will change and from then on, every time you open the jug this issue will arise.

This answer is probably too little, too late - I hope you made out ok.