As I know, my friend got her I-140 approved on May 10th in california center and she filed her I-485 with Texas service center on May 15th and she got receipt notice on May 23rd, from receipt number I am sure it is from Texas since it starts with "SRC". her PD became current in this May and she did not file her case concurrently. This is all I know. It seems a little different from what you said. Anyway, this is the story I know.