Cyclone10LP: Unable to assign pins documented as DIFFIO

Hi,

I am working on updating a design for a 10CL120YF484I7G device. This design has been fielded and as such has been built successfully in the past (last build was 2/28/2022). However, opening the project today I am receiving errors regarding "illegal location assignment" on pins D8, E8, AA6, and AB6.

I have pulled the pin information document for the Cyclone 10 10CL120 device (dated 2019.03.29) and am specifically looking at the F484 section. This document details these pins as DIFFIO_T19n, DIFFIO_T19p, DIFFIO_B7n, DIFFIO_B8p.

I have not updated the Quartus software since the previous successful build (last year). The version being used is v21.1.0 Build 842 10/21/2021 SJ Lite Edition.

The pin planner is showing all four of these pins as dedicated ground. But this cannot be the case per the documentation and previous successful builds.

Any help with this appreciated.

Thanks