From what I’ve heard they’re in no rush. It’s likely going to be another 3 month or so period before we see a new service similar to the original soft launch diagram to this new one
Reading between the lines, they probably need a resolution to the ASLEF dispute before anything can move forward.
Roughly speaking, it bears the same relationship to you local sewage treatment works as does your computer printer to a newspaper's web offset rotary printing press.
Protec (a German maker of such things) claimed the first in service in the UK in 2019, in a Scotrail Class 334 (see thread). But that's just one as a demo/trial, and SWR claimed the 701s as the first full fleet to get them (as, if and when). There's an implication of Protec's silence that they didn't supply them, but I have not found another name.
Interesting - thanks!