Its a bit more complicated than that. Prigozhin has been sidelined for supplies by the regular army. His Wagner troops and the regular army were even rumoured to have had a street battle against each other day over this (yeah I know the irony of wasting bullets on Rus vs Rus fight). Firstly, this is a change in tune because he's now saying that the regular army also have little ammo. This appears to be a complete change of tune, so something has happened, the blame has now gone from The Army to The Kremlin. He's saying there should be warehouses full of ammo and maybe there should be but also its highly likely there may not be. He's getting closer to having a pop at Putin but he isn't there yet because his Wagner troops are also behind the current Sudan situation and the lust for gold. Now some will tell you that itsn Putin that wants the gold but it might just be Wagner, like all the diamond mines they run in Africa too.
It really is quite complicated trying to understand what is actually going on behind the lines and I don't think anyone really knows