Honda Civic 2009 gti rear callipers won’t wind back

[JEA575]

Changing discs and pads on rears, new disc is fitted ok
Tried winding back callipers, clockwise, goes so far back, it turns easily but then stops and spins before wide enough for new pads
Pistons do not have the usual cross slots more like 4 notches,
Any ideas is gti callipers different to videos on line? Or is it handbrake related?

 

[JEA575]

Changing discs and pads on rears, new disc is fitted ok
Tried winding back callipers, clockwise, goes so far back, it turns easily but then stops and spins before wide enough for new pads
Pistons do not have the usual cross slots more like 4 notches,
Any ideas is gti callipers different to videos on line? Or is it handbrake related?

Answering my own question the pistons do wind back in clockwise but had to remove callipers and take them to the bench. In a vice and with lugged tool pushing hard and turning them the thread did catch. My pads were worn down to 3mm so pistons must have extended beyond the helix threads.

All fixed now new discs and pads.