@Seahawks Fan just keep working at it. I was a month and a half in the 250s. If you need to break out of a stall there are 2 ways. Introduce more exercise (intensive cardio workouts) or shift calories to your body. I take it your hitting the gym as you mentioned muscle mass increase, maybe add a little more cardio. Our bodies like to regulate themselves, so by introducing a change you can usually break out of a plateau. Here is a good article explaining it the plateau, https://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/weight-loss-plateau/art-20044615 ,talk to your team regarding the calories (article says to drop them, which we usually can't as we are already low).
I spoke to my nutritionist and she actually is the one who recommend more calories to break out. I was only at about 1000 calories a day and when I told her my workouts she encouraged me to move to at least 1200-1400 daily. I lift 3-4 times a week and alternate jogging every day in between on top of my daily walk with the dog of 1.5 miles. So some days I get in 3-4 miles with the jog and walk. She said that my body was basically going into starvation mode and not letting go of weight because if my exercise routine. I try to keep my calories at about 1300 a day and has been working for me the last 2 months.
Keep up the great work.