slow downs happen all over the place, some generally effect everyone at the same time, but lots are just all over the board individual occurrences. Having a higher starting BMI, you can drop some serious amounts of weight, your call out stats appear to show 100 lbs already since March, which is fantastic.
Pay attention to your BMR, the amount of calories you burn just from being alive. As we age, and as we lose weight, this number drops. So we have to adjust our routine to keep the weight loss the same rate (or just accept the changes)
https://www.active.com/fitness/calculators/bmr
So for you, without knowing your age, I'll just assume 35
Your starting BMR was 3042 calories per day
Today your BMR would be 2607 calories per day
That's a rather large change in caloric burn per day , 435 calories less per day are getting burned, just because you lost 100 lbs.
So, keep tracking your intakes, keep your water intake in the 128oz range if possible, and keep exercising. You'll either need to accept the slower weight loss or change your daily exercise or intake or both to cover the 435 calorie change to keep your original caloric deficit the same.
Hope that helps!