Swapping a hub body on a hub developed for that like the one of Hope, Tune, DT-swiss... is very easy, quick and can be done without tools. Only the cassette removal from the hub body requires specific tools.

Indeed, the A-line is only BSR = 3s IGH.

One more thing: I don't know the Aceofix Brompton clone, but I know some Aceofix Brompton parts that were low quality and not reliable.