I keep it the same, but my breaking the fast time can vary if needed. Ending time is more important to me.
As for how soon, that’ll depend on your caloires in/calories out and your goals. So you should see results pretty quickly, but what those results are will be based on your own individual plan.
Mine is roughly the same. I do OMAD and eat anywhere form 5 pm to 9 pm.
I like to eat earlier in the day but I have kids and sometimes they got stuff going on after school so that’s why sometimes it’s super late, I keep at least 23 hours between my meals