I started with about 50 pounds to lose and hit a "plateau" at around 8 weeks in at about 12 lbs lost and hit a second "plateau" in the last few weeks at around 16 weeks in and about 25 pounds lost.
Scare quotes around "plateau" because I agree with kencc -- they aren't plateaus so much as a psychological human need to see patterns in the data. They certainly FEEL like actual, real plateaus!
The key is to stick to it, to not get frustrated, and to do things like check your TDEE and maybe track your calories for a few non-fast days to see if you might be taking in more than you think. There are other reasons, of course, that might be hurting your efforts to lose weight (an underactive thyroid is apparently quite common among the people in who participate in these forums).
Also, if you are exercising a lot, especially if you are exercising now and you didn't before, your body reacts to stressful workouts the way it reacts to most stressful things -- inflammation. This water retention will mask weight loss temporarily.
Carorees has a great post about "why am I not losing weight when I've been so good?" Check it out:
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