(Link)
(Link)
Lost brass to Sir Robert Ashton, d. 1392, St. Mary de Castro, Dover
Drawing: London, Society of Antiquaries MS 497A. f. 155
The way the head is positioned high under the canopy arch and the position of the sword on these two examples are also paralleled on the lost 1384 brass once in St. Mary de Castro, Dover Castle to Sir Robert Ashton, governor of Dover Castle, known only from a seventeenth-century drawing by Dering (Fig. 7). By the standards of antiquarian drawings, it is of high quality, with many of the hallmarks of Series C work, including the elaborate bottom to the jupon and the splayed feet, being immediately apparent.

London, Society of Antiquaries, MS 497A (Original notes and drawings made by or for Sir Edward Dering of monuments and arms in churches in Kent, 1628-34), f. 55. I am grateful to Nigel Saul for bringing this example to my attention.

(Link)
Sir Robert de Ashton
DEATH 9 Jan 1385, Kent, England
BURIAL St Mary in Castro Churchyard, Dover, Dover District, Kent, England

(Link)
Sir Robert de Ashton, also called "Robert Assheton" or "Robert de Assheton" (died 1385), was a civil, military, and naval officer under Edward III of England who achieved distinction alike in court and camp, by land and by sea.
Ashton arms: Argent, a mullet sable pierced of the field

(Link)