The manuscripts of the French translations of Edmund of Abingdon’s Speculum religiosorum (or Speculum ecclesiae), collectively called (for convenience) the Miroir de Seinte Eglyse  can be divided into two main categories: those designed for a religious readership, and those intended to be read by lay people, with a shorter version of the ‘highly articulate exposition of contemplative prayer’  found in the penultimate chapter 36. Of the religious versions (‘A’ in Wilshere’s edition), A. D. Wilshere identified four which were addressed to female religious.  One of these is found in a British Library manuscript, MS Royal 12.C.xii (hereafter R).
I have just found a full and helpful description of this manuscript on the University of Birmingham’s Manuscripts of the West Midlands website:
This manuscript, from the first half of the fourteenth century, contains a trilingual miscellany. It is not a large book (9 ¼” x 6” with 123 folios): it is a book that could easily be held and read by an individual reader – an individual with a wide range of interests. It contains a romance and a chronicle, medical and culinary collections, political satire, chiromancy, astrology and prognostications, as well as both the speculum of Edmund, here given the colophon  ‘Le livere ke seint Edmund de Punteneye fist e si est apele Speculum amicicie’, and hymns and prayers composed by Edmund.  A full description is given in the introduction to the modern edition of Fouke le Fitz Waryn,  one of the French texts contained in the manuscript. As the editors point out, ‘Royal 12 C. xii consists of eight originally independent units, each containing from one to four quires; these units we shall call “booklets”.’ 
The Speculum, along with a treatise on the Mass following it, is one of three booklets in a textura hand. Most of the manuscript is in an anglicana script and, it would seem, in the hand of the compiler, who was also the compiler of the ‘Harley manuscript’, another trilingual miscellany, BL MS Harley 2253 (hereafter H). Our understanding of R benefits from the study of H and of the Harley scribe, who we know was working in the Ludlow area in the first half of the fourteenth century. R seems to have been compiled over many years; Carter Revard argues for the Harley scribe working on it ‘during 1316-40’.  Revard suggests a possible patron for the compilation of R: Sir Laurence Ludlow, as ‘someone who might be expected to have shown an interst in the romance of Fouke le Fitz Waryn and even to have wanted a copy of it made for the household, in about 1324-26’.
It is the romance Fouke le Fitz Waryn and the culinary recipes  that have attracted particular interest. If we are interested in the Speculum there are two questions that need to be addressed. Firstly, the Harley scribe acquired the text from somewhere, as the editors of Fouke, and Revard acknowledge.  The text is in a textura hand, has the only example of an illuminated initial in the manuscript (at the opening of the text on f. 17r; it is in blue and gold but the image is unclear; Theresa Tyers has suggested the initial is similar to that in MS Royal 15 D II ), and the quality of vellum seems different – heavier? – than that of the rest of the manuscript. It would appear to have been written for another book and a different readership. The question, then, is for whom was it originally prepared. – maybe an institution such as a nunnery, rather than an individual.
The second question is from where the Harley scribe acquired this booklet, and why.
1] Edited as such, Mirour de Seinte Eglyse (St Edmund of Abingdon’s Speculum Ecclesiae), ed. A. D. Wilshere, Anglo-Norman Texts (London: Anglo-Norman Text Society, 1982)
2] Wilshere, Mirour, p. xi, (quoting Forshaw).
3] See stemma on Mirour p. xvii.
4]Definition of colophon in New Shorter OED: 2. A statement, sometimes with a device, at the end of a manuscript or printed book, giving information about its authorship, production, etc.
5] A description of contents is found in George F. Warner and Julius P. Gilson, Catalogue of the Royal Manuscripts, vol. 2 (London: British Museum, 1921).
6] Fouke le Fitz Waryn ed. E. J. Hathaway, P. T. Ricketts, C. A Robson and A. D. Wilshere, Anglo-Norman Texts (Oxford: Basil Blackwell for the Anglo-Norman Text Society, 1975).
7] Introduction to Fouke, p. xliv, with reference to P. R. Robinson, ‘“The Booklet”: a self-contained unit in composite manuscripts’ in A. Gruijs and J. P. Gumbert, Codicologica in Litterae Textuales, Leiden.
8] Carter Revard, ‘Scribe and Provenance’ in Studies in the Harley Manuscript: The Scribes, Contents, and Social Contexts of British Library MS Harley 2253, ed. Susanna Fein, TEAMS (Kalamazoo: Medieval Institute Publications, 2000), pp. 21-109 (p. 72).
9] See, for example, Constance B. Hieatt and Robin F. Jones, ‘Two Anglo-Norman Culinary Collections edited from BL MSS Add. 32085 and Royal 12 C. xii’, Speculum, 61 (1986), 859-82.
10] ‘Perhaps the year after he copied this , or a little later, he obtained a doctrinal and devotional treatise, the Merour d’eglise (fols, 17-30, with chapter headings in his hand), and a tract on the mass (fols. 30v-32v, of which the last five lines may be in his hand’, Revard, ‘Scribe and Provenance’ p. 70.