Medieval cut-and-paste: the rubricator put the red and blue section number "XLVIII" in the wrong place, so the owner of the book cut it out and stuck it in the correct place, lower down the same margin:

(Oxford, University College, MS 55 https://medieval.bodleian.ox.ac.uk/catalog/manuscript_13037)

University College MS. 55 - Medieval Manuscripts

@mssprovenance Gee whiz and I feel guilty for writing in the margins!
@mssprovenance
It's how they made corrections
I don't think they did it when they were paid to translate the bible
Think about that
@mssprovenance I love seeing the drawn column margin guides, so I am really surprised that they [didn’t] simply add an annotation (say with an swooping arrow) to where the original annotation should be placed. Were drawn arrow indicators “not a thing” in that time? Would it not be understood. I’m just thinking that cutting paper/velum(?) would be avoided because its so expensive.

@innuendo Medieval people were creative, and had various ways of dealing with misplaced text. Here's a favourite:

British Library, Arundel MS 38 fol. 65 (https://www.bl.uk/catalogues/illuminatedmanuscripts/ILLUMIN.ASP?Size=mid&IllID=11246)

Image of an item from the British Library Catalogue of Illuminated Manuscripts

This page describes and shows an image of an item in the Catalogue of Illuminated Manuscripts

@mssprovenance Thank you for sharing this. I agree, it is delightful.