You're doing fantastically well!
If you do find that you're in a plateau, I'd recommend switching up the calories and doing calorie cycling. Sometimes our bodies hold onto water for various reasons and the weight may not show up on the scale, so we could be losing inces....you may want to take some measurements since the scale is only one type of an indication of how you're doing. Also, remember that up to 1-2 lbs. a week is not true for everyone. I think that sometimes, if people get into a certain weight category, it changes hormone levels, and the "rules" of deficit calories that would apply to someone who hasn't been of such a weight wouldn't necessarily apply. I hope I'm making sense. The key is not to get discouraged. I think a lot of people drop out of the weight loss journey simply because they don't feel like it's moving fast enough. Congrats to you!
First goal: under 180:
Second goal: 175 or below:
Third goal: 168 (no longer overweight):
Fourth goal: 160 or below:
Final goal: 145-155 (not sure if this will ever happen):