A Handbook of Dates For students of British History appeared in a new edition in 2000; C R Cheney and revised by Michael Jones*. They wouldn't get away with that title nowadays, because, while the book gives the Regnal Years of English monarchs, it appears entirely ignorant of Scotch kings ... not to mention Welsh princes. It really is a trifle parochial; thus, it only gives Julian Easters down to 1752, when we went Gregorian, although it would have been useful (despite the self-limitation of the title) in the one volume to have continued the Julian information down to the present and beyond.
It does provide the complete layout of the unique year 1752, when the people of England were deprived of eleven days of life as September was reduced to a mere nineteen days so as to bring us out of the old Julian Calendar and into line with the Gregorian Calendar of Western Europe.
And now these Three Kingdoms (as we used to call them before they were renamed the Yewkay ... I have found the older usage surviving in literature as late as the 1930s) are due to slip their European moorings and slink off into mid-Ocean in the hope of striking lucrative trade deals with the lost continent of Atlantis. No longer will the right wing Press be able to inspire terror at such thoughts as EU standardisation of the shape of bananas, Imperial being replaced by Metrical, and all that.
But what nobody, even the Daily Mail, has advocated is going the Whole Hog by resuming use of the Julian Calendar. "Thirteen additional days of Life! A longer Summer!! A two week August Bank Holiday!!!" What's not to like? It wouldn't matter if a subsequent British Europhile regime reversed such legislation as long as in doing so they snipped the thirteen (or fourteen?) days out of the middle of winter. Who would resent being deprived of a fortnight in January? It would be a win-win situation.
You know it makes sense. Everything I suggest invariably makes sense.
Paperback, Cambridge University Press, ISBN-10 0-521-77845-X