From Sigma:
This firmware corrected the phenomenon related with the selection range of AF frame (AF point) of the camera.
For customers who own the SIGMA USB DOCK and applicable product listed below, please update the firmware via SIGMA Optimization Pro. Before updating the firmware, please ensure SIGMA Optimization Pro has been updated to Ver.1.5.0 or later.
Applicable products
Benefit of the update
SIGMA Optimization Pro Download page
Note: For those using any of the above lenses with the SIGMA MOUNT CONVERTER MC-11 EF-E, you'll need to update the mount converer's firmware to work with the lenses' new firmware.