Looking at the sagging antennae, I think it is tired and maybe let its palps sag too ? The forewing post-medial pattern is a good match to that in Ken's photo on Coffs Butterfly House webpage.
I'm still not sure. This moth looks more elongate to me than most S. viridis. The post-medial 'C' or 'sickle-shaped' marking is common to many Oecophoridae. This moth does not appear to have striated antenae as have many of the S. viridis examples I see online - including in K. Harris' photo on the Lepidoptera Buttterfly House website. But I don't have a better alternative to offer either.