Gaining weight while on a calorie deficit?


New member
I've had a break in anything fitness whilst working from home and gyms being closed and gained a ton of fat. Around 25 or so pounds.
I've been training at home with small weights for the past month or so and have been making good progress (218.4 lbs to 207.8 at my lowest yesterday). I used to be big into the gym prior to the pandemic and was pretty fit with significant muscle mass. Just recently gyms opened up and I started going again and doing strength training (5 days of strength training since openings). I was using a scale daily but noticed that for the past 3 days my weight stalled at 207.8, with it going back up to 208.8 this morning (after using the bathroom and not eating). All my measures were done under the same circumstances as well.
My diet is in a calorie deficit with me being 6"1' and 208lbs, I'm cureently at 1850 calories. 205p/156c/39f. I'm 23 and a male by the way.
I was just wondering whether it is a possibility I'm gaining back muscle that atrophied over the duration of the pandemic, or could it be something else?