
It looks fresh enough to have emerged this month, and I really cannot see how this can still be part of the same single generation that started back in May. Surely this has to be a second brood - otherwise this individual was a caterpillar throughout last winter, pupating at some point between spring and just a few weeks ago, therefore spending pretty well a whole year over these two stages of its life. Maybe that is what has happened, but it does seem unlikely.
Dave