Phospholipase that hydrolyzes phosphatidic acid, including 1,2-dioleoyl-sn-phosphatidic acid (PubMed:9488669). Required for the organization of the endoplasmic reticulum exit sites (ERES), also known as transitional endoplasmic reticulum (tER) (By similarity). 1,2-di-(9Z-octadecenoyl)-sn-glycero-3-phosphate + H2O = (9Z)-octadecenoate + 2-(9Z-octadecenoyl)-sn-glycero-3-phosphate + H(+) Forms homooligomers and, to a much smaller extent, heterooligomers with DDHD2. Interacts with SEC23A and SEC24C. The measured range is 1-835. Belongs to the PA-PLA1 family.