Did some more troubleshooting and found the issue.
Bad BRAND NEW access point.
Was not sending/receiving B channel in mixed mode.

When I troubleshot before, I saw signal strength when in the mixed mode.
However, the signal I was seeing was NOT mine - probably someone in our neighborhood. I retested early this morning and saw NO B signal (guess my neighbor
was still in bed, hehe)

Replaced the access point, all is well now!
Chris