Thick Brick Wall!!! lol

I have hit a brick wall and need advice. Looking at old church records for my great grandfather, Teodoro Escobedo, it shows "AP Estevan y Francisca Lozano" which I've always assumed meant his grandparents were Estevan Escovedo and Francisca Lozano (maiden name). However, with the help of that link I put up I found a church record for one of Teodoro's brothers, Enrique, but it was listed as follows: "Enrique Losano" and "AP Estevan Losano y Francisca Lira". It also shows Teodoro's father as a Losano, Gabino Losano, which has confused me. My question is "AP" stands for abuelos paternos right? That would be the grandparents of the person being christened or born, in this case Teodoro right? Or would AP be an older ancestor and am I missing an ancestor? I was told our family came originally from Jalisco but most of these, in fact all, are in Zacatecas which I knew we also came from, just not this far back. Were there a lot of mistakes on the old church records? They have always seemed to verify what I was told by my grandfather and this has confused me. Thanks for any advice or help.

Robert Escobedo