It makes little to no sense that the body has a natural energy storage system and that it would then preferentially go into catabolism rather than utilise its adipose stores. Unless you are bouncing around 4% or less fat levels then why would the body catabolise itself? There is some lean mass loss associated with weight loss unless you are on a training regime as it physically takes less effort to move around a lighter body. So why would the body not rid itself of additional lean mass that is no longer required to perform designated tasks. But this scenario is distinctly different to catabolising itself to access stored energy.

Your glycogen stored should be reasonably topped up first thing in the morning as you’ve had all night to top those stored up.