I recommend dropping your calories by 100 weekly/200 bi-weeklyish until you reach 500 below your maintenance (not the 1400), then have a week at your maintenance before repeating.
The amount of weight lost within a set time will be different for everyone, its recommended to only lose around 1-2lbs a week though. Also the time you stop eating doesn’t really matter, fasting only works because you’re limited to eating within a short period so you are in a calorie deficit anyway x