Mea Culpa. 😬
I have been slack and haven’t removed the screen to clean for a few weeks.
I generally have my second coffee, turn off the machine, think “I’ll just let that cool down before I clean the screen” and promptly forget.
I don’t know why as the whole process takes about 3 minutes.
The top of the screen was filthy as was the lower 15mm or so of the bore.
This must be the travel limit of the lower piston seal.
I occasionally use top paper filters and do use the auto stop function.
It all came off in a moment with a wipe of a bit of sponge dipped in the Cafetto cleaning solution.
I got so enthused that I cut a disc out of a bit silicon mat and back flushed the group via the manual release.
Easy Peasy.