Doesn't really seem like anything new. It's been their position for decades that there different terms standing for the same group, depending on what role is emphasized.
"Faithful and Discreet slave" refers to all the anointed, in their role as "suppliers of spiritual food".
"Domestics" refers to the same group, but in their role as "receivers of spiritual food".
Of course, the writing style is muddled so that it's easy to get confused. I think they do it on purpose, so people have a tendency to not think too deeply about it and say "Well, they're deeper thinkers than we are, so they must have it right!"