Atleast thats what I believe. Some people will disagree but muscle cells dont just randomly shrink, yes bloating added glycogen stores and other factors will make it appear you lost your gains but if you dont pct correctly, eat poorly and screw up your lifting you will loss all of your gains.
Just let it be known that your weight will increase on cycle but that does not mean you are gaining muscle, you have to lift, eat and sleep to do that not just take a pill.