Morden Hall Park frustration 5th September 2017

Though more in hope of a miracle, and without a camera, I had 15 minutes in Morden Hall in between the showers. With nothing seen except a Robin and parakeets up till a stream, I was about to go back when I spotted a woodpecker-like bird fly from the ground under some trees up to an angled tree, which made me look twice. It then went round the tree, then flew off South. The most frustrating thing is that on first glance it looked like a Wryneck - something which I have never seen before, but was such a brief sight that I couldn't get a detailed look. 
A few metres on, a small warbler was leaping around in a bush. It looked like a Chiffchaff, but quite pale and an odd long bill. When I approached it, expecting to see it dart off, it stared at me for 10 seconds from 3 metres away.  Another problem - no camera, so the only picture I got was an awful phone picture. It then flew off into a hedge not to be seen again. My impression was almost of a Dusky Warbler, but that was just excitement and I know that it was a youngish Chiffchaff. 
On the way out, a Kingfisher flew by and a Little Egret was wading in the distance. 
Very frustrating. 
This morning I found this butterfly in the garden, but I can't tell what it is I have never seen an outerwing like this before. If you know please comment below.

butterfly sp.