It could be fat, but from what I've read and what makes the most sense is that putting yourself in a deficit during the time that your body is recovering is just asking to lose muscle. I'd rather wait a few months after my PCT has ended and given my body a good amount of time to fully "recover" before doing that. Although it would be nice if I could just cut now! I was 5'9" 160 legit single digit bodyfat and now 210 a good bit fatter but also way bigger than I was on my last natural bulk when I was in the 190s.