Why is P20 fighting position with P15?

I was P16. P20 was a lap down and fighting position with a driver at p15. Why? They made contact and off the track. Allowing me to close him P15 down. He made a mistake at the last second turn at the Fuji track. I knew he would exit wide and I made sure I was pointing straight at the apex. I over took him from the inside. Gained 5s over him. Finished the race at P15 from P19 at the start. Finally got my B1 safety rating in 4 races.