^ this is what happens. When i started working out i lost a shitton of fat and gained muscle over like 2 years about what i lost from fat. For the whole time I just recomped not gaining or losing much weight but massive change still. Maybe this is more the case for men since we have high androgens and build lots more muscle? Interested to see how it differs in women.
Even men have a hard time putting on a pound of muscle per month after the first couple of months of training. You must've been very dedicated if you managed to replace a "shitton" of fat with muscle. I don't think the average gymgoer can expect that to happen.