Correct. If you fetch mail, you're vulnerable (at least that's my understanding).
You can use third-party apps, or Safari if it's a webmail.
You would need to read mail with a third party app.
You can still manually fetch the mail.
Manually fetching would still execute any malicious code contained in the mail if I understand the article correctly. The only way to be protected seems to be to not use Mail.app until iOS is patched.