I think they mean concepts like morning and evening, or day and night would remain. The difference would be that in London, midnight would be 12:00am, but in San Fransisco, midnight would be… 16:00 / 4:00pm. Each timezone would have to adjust the numbers, in the same way the southern hemisphere considers January to be in the summer.
Chicken just isn’t gonna need to be that precise. It’s not an ingredient that mixes with others in that way. That being said, chicken is an item that most recipes would mention by weight. Nobody is going to actually weigh out the chicken; they’ll just go with a close measurement, or use potentially use the packaging it came in for reference.