I wonder what timezone the containers think they're in?
But then time is faster (relative to us) because it is higher up in the gravity well.
https://www.telegraph.co.uk/news/science/science-news/802098...
So which one wins out?
https://en.wikipedia.org/wiki/Time_dilation#/media/File:Time...
However, both effects can be ignored for almost all purposes. The effect of time dilation is less than 1 part per billion, which is basically undetectable without an atomic clock.