My iPad says 35 passwords found in data leaks

I'm not sure I understand entirely. I have Detect Compromised Passwords enabled. iCloud Keychain was NOT enabled for autofill and only 1Password 7 was enabled. However lately I noticed my iPad was offering to autofill from a non-1Password source. I do not understand how the now 45 compromised passwords got into the iCloud keychain as I had it set to autofill for only 1Password. Could this have occurred when the newest version of 1Password 7 came out. I find myself using both versions as I didn't remove the original version.

I'm also baffled about some of the "compromised passwords". Some of the login names shown in my latest alert had email address logins listed that no longer exist. When I set up 1Password quite a few months ago (maybe a year ago?). - I changed every password on its website and also every email login if the email changed. If I didn't need a login anymore - I closed the account. It took a week to change every password, close accounts no longer needed and to delete every saved login/password from known password keepers from browsers. I just checked Google and the only saved one was Amazon. I just deleted all 45 compromised passwords from Settings > Passwords. I am concerned - I don't understand where my iPad is getting this data from. Chances are that since some of the data appears outdated it's not an issue since I changed every single password when I changed to 1Password months ago, but nowadays one shouldn't leave things to chance. I don't want to have to change every one of my passwords again. I'd like to understand where this data came from. It sounds like I have things configured correctly. Dunno, I am so not a techie. Is there a bug that switches on iCloud Keychain or asks users to turn it on in a manner where one wouldn't under the ramifications.

Once again, thanks for any clarification you can provide for this baffling concern.