weight loss after moving

elenabab

I have been losing weight since january and have lost 20 lbs. i moved and went for about a month without a scale. I was shocked to have lost 8 lbs while moving without really doing anything extra (other than loading/unloading cleaning, and not having my usual exercise) = 142 lbs = goal weight. I also went from swimming 2-3 times/week x 1- 1.5 hours to biking about 30 miles per week. I biked 55 miles this weekend. Eating essentially the same diet, getting adjusted to a new job, just finished a month of night shifts. Since my low weigh-in 2.5 months ago, i have gained 8 lbs back while eating essentially the same. My scale is also reading my body fat anywhere from 25%-29% whereas before I was consistently at 32-33%. I am having a hard time believing that this is all muscle gains. Am I just retaining more water since its summer and its been hot? Is biking not enough exercise? Do I need to go back to tracking every single food and cut down to 1200 calories per day? Would appreciate any advice, because I am perplexed...