|“The Rule in general observed among Printers is, that when a Book happens not to be ready for publication before November, the date of the ensuing year is used.” — John Nichols, Literary Anecdotes (London, 1812) iii, p. 249n. According to Philip Gaskell, Nichols is describing 18th century practice. Evidently the custom dated somewhat earlier as per this example.
Narcissus Luttrell corrected the imprint date in his copy of Francis Manning’s Panegyrick (London: Printed for J. Weld, 1698.) Call number: (Ex)3598.999q vol. 64, no. 4.
Another example: Inscribed on title page ‘Angelsey. The guift (sic) of the author. Dec. 19, 1674.’ of Winston Churchill, Divi Britannici: being a remark upon the lives of all the kings of this isle, from the year of the world 2855. unto the year of grace 1660. London, Printed by T. Roycroft, to be sold by F. Eglesfield, 1675 (Ex DA130.C56q). The recipient was Arthur Annesley, Earl of Anglesey (1614-1686)