That's a gearbox off job. Glad it's under warranty, bit expensive otherwise!
I change my clutch/brake fluid every two years to prevent slave cylinder/wheel cylinder problems.
A garage shouldn't charge much to do it if you don't fancy it yourself, just a case of pumping in fresh fluid.
False economy not to do it.
B-Max Nav Titanium 1.0 125bhp manual, privacy glass, reversing camera.