@DianneClarke I collected the cocoon on 4 Oct. I saw a few of them that day. Anecdotally, there seems to be a glut of moths this past month or so. A few people are telling me they've been invaded!
There seem to be an abundance of these this season - I have had up to 14 in my little backyard. How long did you have the cocoon before the moth emerged? I kept one for 12 months with no moth emerging.