Just repeating yourself doesn't help.
I mean undifferentiated with regard to person. With God called Father so few times in the OT (a much bigger corpus of material than the NT), it's simply not a prominent designation, and the faithful OT believer would have thought of יהוה as אלהימ, not אב, and certainly not אבי!
For accuracy, 13 times in the OT, over 150 times in the NT, and 30 times Jesus refers to God as "our Father." Of course, when he refers to God as his own Father, he gets quite the reaction...John 5:17-18.