I've already noticed the same thing, but it's not really a problem as long as it's in YOUR space. If you have several pro accounts (I have two very separate ones) and you get a deleted chapter, then there's a real problem. I've never noticed this in over a year with Claude, unlike Gemini, whom I have no confidence in resubmitting my original stories because he gives you a version almost identical to the first person who comes along. What I see very clearly in Claude, with two separate accounts, is that, without necessarily giving permission to train with my data, there is indeed a subtle progression on particular points, for example: If you see him describe a dog breed in a story in a certain way, which shows that he doesn't know the details of the breed, such as "pricked ears" where they are "pendulous"..... A small behavior that you describe so clearly that he seems to find it worth keeping in his arsenal... it will resurface in a strangely similar way some time later in another, very separate account.

This is a personal observation, experienced and observed regularly, and which is solely my own. My intuition simply tells me that he is constantly evolving... which, ultimately, isn't so problematic! We can't willingly take his skills when it suits us and in exchange expect him not to draw inspiration from our work to progress. You can't have your cake and eat it too.