All mails to Yahoo are deferred or in spam
Solution 1:
You can't do much as you got trapped inside the anti-spam of yahoo, the fact that it's yahoo users that flagged your email as spam is a red flag to me. It's not a spamassasin rule(s) that got you, but manual submission to the junk folder.
You should monitor what kind of newletter you send, or why it got flagged as spam. Even if you change your IP, domain name, etc.., if the reason you got human flagged is still there, the delay will follow you.
That message kinda said it;
temporarily deferred due to user complaints - 4.16.55.1