Take it to a brand consultancy, and it'll turn into “Universal. Time. Coordinated.”

I see it, more specifically, as "Universal Time, Coordinated". It never struck me as an acronym that demanded explanation in English.

Interesting. I always think of it as the Universal Time Coordinate. Probably because I've done a lot of work in inertial coordinate systems (where the earth rotates in the coordinate system versus the coordinate systems rotating with the earth). Inertial coordinate systems have four dimensions, time and three spatial coordinates.

But historically there were Universal Times, several of them, and this was the coordinated version of them.

Either one works, as long as the T is at the end. They both feel equally natural to me.