The question is unusual, but consider daylight savings time. There were some complaints about some Apple devices not managing the time change properly, and as I recall Arizona doesn't observe the bi-annual time shift. Moreover, my own company has this year said we will no longer observe the time shift for the sake of dealing with overseas plants, but my desktops (computer clock function) shifted an hour like most do.
Microsoft put out
an article about how to deal with it.
So while "calibration" may be a term used loosely, many of us do consider the term to describe checking a unit's status against a known and adjusting as needed. If it's important, it should be done on a schedule.