If the "co-signer" is signing the note then they become directly liable for the debt. The Notice to Co-signer even tells them that the debt can be collected from them without the creditor fist trying to collect from the borrower.
Based on that I would say they are covered, or at least I would treat them as covered. If they are a guarantor, signing a separate guaranty agreement, then I would look at Andy's logic to determine when they become liable and only your guaranty agreement can answer that question.
The opinions expressed are mine and they are not to be taken as legal advice.