If you already applied, i believe informing CIC about your wife score will be useless; on the contrary, it can delay your application. Also, i believe you would get your PR by October (hopefully before). So, if I were you, i would stick with my current employer for 2 months more.
By the way, i have a friend with a closed work permit and claimed 50 points as well. He left his job 15 days before receiving his PR (specifically 15 days). I'm just trying to let you relax, because i believe if you passed the eligibility, you will get your PR no matter what. However, it's better to stay in the save side to avoid any circumstances in the final review of your application.