It appears that L21-20 whips are being created when L6-20 type rPDU's are selected. Multiple rPDU options were selected, but all created L21-20 whips with 3P CB's, rather than the desired L6-20 whips with 2P CB's.
I have created a copy of the solution for your review (ISX0001367590-0001). I have used edit ATO to fix the original (ISX0001338675-0020).
This could be an older known issue (I just don't work with L6-20's all that much these days . . .).