I noticed a thread about late Peacock larvae, I found c20 larvae at Grove Ferry, Kent this week on nettles. I presume these are very late. Will they overwinter as a pupa.
I believe late Peacock larvae emerge as adults in late autumn, when they have little chance of finding enough nectar sources to allow them to overwinter. There were some reported near here (north Somerset) last autumn.
There was an adult nectaring on marigold in our garden around 8 November last year that could have been a second-brood Peacock, though equally it might have been a hibernator tempted out by the sun.