Nightmare of a brake problem - FZ6 S2

[Shinigami]

It does slide on the pins by hand but not visually when the brakes are used, I'll try testing the line like you say, piston is spotless and visibly retracting as can see in the video if its not chucking it down tonight will test a few more things

Failing that anyone know a decent garage in Manchester who know their brakes? Rather fix it myself but think Mrs is getting bored of me nicking her CBF lol