The SPINOR_RX and SPINOR_CSn pins on the v1.1 schematic sheet 3/7 are the wrong way around. I took a while probing with a 'scope to find that the correct assignment is swapped around, i.e. counter-clockwise from ETH RXN, pins should be SPINOR_RX, SPINOR_CSn, GND, SPINOR_SCK, etc. Would it be possible to update this with the next release of the schematic?
Thank you for your thorough research, we will correct this error in the next version.