non requested string translation in timestamps

[Cédric Martínez Campos]

Hi there!

When I add a timestamp through, for instance, scheduling (C-c s), the
day abbreviation is translated to my local language, that is, Spanish.
However all calendar variables, calendar-*, and, more specifically,
calendar-day-{name,header,abbrev}-array have not been modified and
keep their default values in English.

I would like to know how is this happening. Is this a bug or somehow intended?

Thx in advance,
Cédric M. Campos

Version: Emacs 28.1
Mod: Spacemacs 0.999 (fully updated develop branch)
Distro: Manjaro 21.3.3 / Ubuntu 22.4 LTS