Early Hibernation?

This 'pillar yesterday, Sat October 19th, was fully coloured up (complete with bronze V) and in pre-hibernation pose - about to quit the leaf for bud or stem (unless it had decided to hibernate on that terminal leaf).

Crucially, it had little choice as its sallow tree was 99% bare due to the ravages of Melampsora Willow Rust. How it had fed up to a decent hibernation size on such a depleted tree only the Good Lord knows...

Here's it's tree - 

For the record, the earliest dates I've recorded larvae in hibernation are 17/10/2010, 21/10/2016 and 23/10/2009 - all on early leaf-fall sallows.