Btw the head gasket 'failures' on these almost always only leak oil externally. It can be lived with for as long as you can stand the mess on the garage floor and almost never leads to overheating or milkshaking, and as I mentioned even this can be remedied with a retorque.
I feel that we are lucky living in warm weather climates because it means our engines undergo significantly less thermal expansion before reaching operating temperature, and it's normally this thermal expansion that aggravates head gaskets until they let go.
If it hasn't been addressed already, it may never need attention.