A modest calendrical proposal.

In the Left Hand of Darkness, Ursula Leguin started the action with a brief reference to the Gethenian calendar.

"It is always the Year One here.

Only the dating of every past and future year changes each New Year's Day,
as one counts backwards or forwards from the unitary Now.

So it was spring of the Year One in Erhenrang, capital city of Karhide, and I was in peril of my life, and did not know it.

In Karhide/Orgoreyn years are not numbered consecutively from a base year forward to the present;
the base year is the current year.
Every New Year's Day (Getheny Thern) the year just past becomes the year "one-ago,"
and every past date is increased by one.
The future is similarly counted, next year being the year "one-to-come," until it in turn becomes the Year One.
The inconvenience of this system of record keeping is palliated by various devices,
for instance referring to well-known events, reigns of kings, dynasties, local lords, etc."

A good idea, quite compatible with friendly machine implementation.

A javascript test calculator for now based dates.

A more ambitious viewer which attempts to parse and reform the dates in other pages.