At 11.05 this morning Y3 moved to the rear of the nest.
A few seconds later she fledged. She could be seen flying strongly over the block of timber behind the nest.
As you can see in the clip Y1 joined his sister soon after the fledge and a couple of minutes later Y2 left the nest too. Ospreys could be seen flying but identifying them is another matter! An image from just before Y2 left his perch.
Y3 hasn’t returned to the nest at the time of writing (12.30). Mrs YA flew off with a fish a few minutes ago and may be trying to lure Y3 back.