Can you spot the bird? (Patreon)

Writing from the airport on my way to the UK for my ecotherapy training... Braving the storms there I go!!! For those of you in the UK I'll be greeting you in spirit on my arrival!

These pictures are from two days ago, such a lovely dip! Freezing cold, with sun at least! And unidentified bird on the apple tree near my swim spot.

For birds lovers ... It was tiny, but not a wren, it wasn't so dark... White/clear chest, jumping from branch to branch, single frequent sound... Any ideas? Can you see it in disguise on the branch?