Canterbury, England.  AD 999.

An atmosphere close to panic prevails today throughout Europe as the millennial year 1000 approaches, bringing with it the so-called "Y1K Bug," a menace which, until recently, hardly anyone had ever heard of.
Prophets of doom are warning that the entire fabric of Western Civilization, based as it now is upon monastic computations, could collapse, and that there is simply not enough time left to fix the problem.

Just how did this disaster-in-the-making ever arise?  Why did no one anticipate that a change from a three-digit to a four-digit year would throw into total disarray all liturgical chants and all metrical verse in which any date is mentioned?  Every formulaic hymn, prayer, ceremony and incantation dealing with dated events will have to be re-written to accommodate three extra syllables.  All tabular chronologies with three-space year columns, maintained for generations by scribes using carefully hand-ruled lines on vellum sheets, will now have to be converted to four-space columns, at enormous cost.  In the meantime, the validity of every official event, from baptisms to burials, from confirmations to coronations, may be called into question.

"We should have seen it coming," says Brother Cedric of St.  Michael's Abbey, here in Canterbury.  "What worries me most is that 'THOUSAND' contains the word 'THOU,' which occurs in nearly all our prayers, and of course, always refers to God.  Using it now in the name of the year will seem almost blasphemous, and is bound to cause terrible confusion.  Of course, we would always use Latin, but that might be even worse-the Latin word for 'THOUSAND' is 'mille'-which is the same as the Latin for 'mile.' We will not know whether we are talking about time or distance"

Stonemasons are already reported threatening to demand a proportional pay increase for having to carve an extra numeral in all dates on tombstones, cornerstones and monuments.  Together with its inevitable ripple effects, this alone could plunge the hitherto-stable medieval economy into chaos.

A conference of clerics has been called at Winchester to discuss the entire issue, but doomsayers are convinced that the matter is now one of personal survival.  Many families, in expectation of the worst, are stocking up on holy water and indulgences.