I am glad you asked… I believe I communicated with every support person. I finally got someone to return and replace the unit.
No one was able to confirm that the MPPT was blown. One support person said it was protected. I asked for a test or a diagnosis but then I had AC error codes and my 110 plug came apart.
Based on my research follow the MPPT protocol although there is some confusion over the split MPPT.
My unit started tripping breakers and GFIC circuits. Error codes 025 and 026.
I can only figure I had a bad unit and hope to have the replacement to prove the AC300 is what I thought it was.