General Hospital was the first (that I recall) to venture into the spin off series category with Night Shift. I remember it being quite successful on SoapNet. Now, Days seems to be doing well with its limited series, Beyond Salem, at least it seems so as it was picked up for a second installment. 

Is there potential for YR and BB to develop their own programming of this style? I do feel like Days and GH both have the best reach for these types of shows, as they seemed to do well in the key demo through the 90s and early 2000s. I think there's a market for those that may have stopped watching around then for whatever reason but might still have nostalgia about their soaps and are young enough to be on streaming platforms. I know that YR and BB also perform/ed well on these demos but the audience just seems older and more traditional to me - but I may be wrong. 

Just to add to this. I would love for GH to do a special series with fan favorites for its 60th anniversary.