I don't think changing passwords and posting patterns for the better is a reason to say someone has changed hands. In my opinion, any user can change their password and email for security reasons, but indeed people will be suspicious when the user has just been active for a long time.

In this case I understand why you suspect len01, but I think you should consider the reasons why he should change his account password. Digital devices such as laptop and flashdisk are quite susceptible to damage, so there might be a good reason. len01 can also prove he has an account if he can sign message from an ethereum address, but for something like sending coins/tokens from that address then I think he should create another wallet and post his tx here. So don't force other people to do it from a btc address after they tell you about losing access to the wallet, while len01 can also prove it with an ethereum address. Try to lighten other people's problems and I think it will be good to consider wisely. But wait, I have nothing to do with len01, but here I am just expressing my opinion.