In Collections for a history of Staffordshire (1903), via the Internet Archive, I have found an entry that may or may not relate to a direct ancestor of mine named William Fletcher:
Staff". John Averey, of Penkrich, milner, and Thomas Hempson, of Penkerich, taillour, were attached at the suit of Robert Kyng in a plea that, together with William Fletcher, of Pynkerich, fletcher, they had broken into his close at Penkerich on the 2oth May, 13 E. IV, and had trodden down and consumed his wheat, rye, beans, peas, barley, oats, and grass with horses, oxen, pigs, cows, and sheep, and for which he claimed ,10 as damages. The defendants appeared by attorney and denied the trespass, and appealed to a jury which was to be summoned for three weeks from Easter. A postscript shows no jury had been summoned up to Easter term, 18 E. IV. m. 108.
My understanding is that Pynkerich/Penkrich/Penkerich is modern day Penkridge in Staffordshire.
I can read a day of 20 May from "2oth May, 13 E. IV," but does the remainder provide the year?
In another place in the same document, another possible direct ancestor named Thomas Fletcher is also mentioned:
On the Octaves of St. Michael. 14 James I.
Between Thomas Fletcher, complainant, and Thomas Skrymsher, armiger, and Anne, his wife, deforciants of 2 messuages, 2 gardens, 2 orchards, 30 acres of land, 3 acres of meadow, 10 acres of pasture, and common of pasture for all cattle in Asheley, Meare, and Muckleston.
Thomas Skrymsher and Anne remitted all right to Thomas Fletcher and his heirs, for which Thomas Fletcher gave them ^100.
My understanding is that an Octave:
is the eighth day after a feast, reckoning inclusively, and so always falls on the same day of the week as the feast itself.
so I will be trying to interpret the date of "the Octaves of St. Michael. 14 James I." as a second exercise.