The thing is, and people often don’t appreciate what I’m about to post.
Firstly, if he’s subject to such a sentence he’ll be approaching 60 (at the earliest) if he’s released. He’ll be completely institutionalised, won’t know anyone, he will be completely isolated and won’t be able to function in society, and have no means of supporting or bettering himself. He will be utterly frightened and a complete shell of a man. I’d actually be amazed after all that time if he’d even want to be released.
When someone spends that long inside, especially from such a young age, it completely breaks them.
I think people have this notion of prisoners being released after several decades inside skipping away from the gaol and living a happy life of freedom. They don’t. Most of them absolutely hate it after that long inside.
Their sentence doesn’t end if they get released, and nor should it.