Working two jobs when transitioning from F-1 OPT to H-1B

I’m currently working two full-time jobs at companies A and B under F-1 OPT. Both companies registered me for the H-1B lottery. I was just informed that my H-1B registration for company A was selected, but not for company B. When filing the H-1B petition for company A, do I have to stop working for company B to not hurt my chance of approval and when would be the best time to stop working for B (e.g., ASAP, before the H-1B petition for company A is filed, before Oct 1)? Or can I still work for both companies until Oct 1, when I can only work for A until USCIS issues its case filing receipt to B’s concurrent employment petition?

(I am aware of the H-1B concurrent job policy, just wondering whether I can work two jobs from now to Oct 1).
Thank you very much for your help!