[bdibs]

There's a counter on Master Password, so if the password expires or you need to change it, you just +1 and it's new.

They also have settings depending on password requirements (no special characters, etc.).

I'm unsure what the URL really has to do with it, you could just generate a new password for the new URL and change it.

[loeg]

Sometimes different URLs share credentials (LDAP). Changing isn't necessarily an option?

[bdibs]

I guess in a situation like that you'd just choose the base URL you'd remember best.