The Special addresses are used only on CPC 664/6128 and only if the Vortex drive includes an FDC chip.
The pictures of the PCB are not clear. There appears to be a jumper and a PAL type chip next to the FDC.
The manual mentions a 'decoder-ROM' so perhaps this is in the PAL?
* Note1: The -Z and -X drives do not include FDC chips.