The issue here seems to be two different definitions of time. There's "physical" time, i.e. a continuous line and there's human/calendar time which is different

The issue here seems to be two different definitions of time. There's "physical" time, i.e. a continuous line and there's human/calendar time which is different and is most definitely tied to a location. For an example, see http://en.wikipedia.org/wiki/February_30#Swedish_calendar http://en.wikipedia.org/wiki/February_30#Swedish_calendar . (No wonder that time zones complicate things enormously.)