'The Young and the Restless' has pulled numerous character switcheroos through the years, which makes it no different than any other soap. The idea behind multiple actors portraying one character, at various points in time, has existed for ages. That method is generally accepted by hardcore fans, as long as the departing actor is replaced by a competent, compelling colleague. And so, Cady McClain arrives in Genoa City.
Cast changes are one thing. However, multiple roster substitutions within one interwoven storyline in a very short amount of time is another. It's okay if the reader wants to grab a tablet (paper, or digital) in order to create a diagram for future reference.
Billy Miller wanted to moonlight. But, he didn't want to assume Bruce Willis' lead in the remake of that vintage 1980's detective series. Instead, the former 'Billy Abbott' wanted the ability to occasionally work without his YR clothes and apparently was told no. So, he exited stage right (or rather, off the side of the road) with Michael Muhney.
Hardcore viewers haven't been lying in the bed aside of 'Phyllis Summers Newman' for months on end. So, they've already read every shred of information about the unexplained scenario that led to the non-death of 'Adam Newman'. Therefore, there's no need to elaborate on that plotted point any further, at least for now.
Even though Miller moved on, 'Billy' still escaped from the black SUV and managed to crawl all the way home. The battered face of David Tom (the former and now current 'Billy') was miraculously saved.
Now, 'Billy' had grown closer to 'Kelly Andrews' after 'Delia' was killed. But, that chemistry developed between Miller and Cynthia Watros long before Tom and McClain ever met on the YR set.
Watros was working without a contract because she (and her temporary employer) knew that the new MTV show 'Finding Carter' might get picked up and it since has. So, there's no dispute, or unusual backstage story involved in Watros' semi-planned departure. As for McClain, she's a daytime veteran ('All My Children' and 'As the World Turns'). So, viewers should be fine with this rebooted role.
This entire tale does create an important question: Didn't all of the above information read like a soap opera story? Simply swap the actor's names with those of some daytime characters and no one would ever know what's real and what's fiction.