SAB Castle Lager unavailability

For some reasons unknown to me, Castle Lager (500ml cans) has not been available at the regular shops where I shop (PnP, Checkers, Tops, President Liquor, etc.) for some weeks now. A week ago, the manager at President Liquor had no stock but promised that he would source stock before their promotion ends, but when checking with him on the last day of their promotion, he confirmed that he tried all his sources and they all confirmed that Castle Lager (500mk cans) are not available at any depot. I find this totally unacceptable, and also find it unacceptable that all managers at the stores where I checked, confirmed that they were also kept in the dark about the reason for this scarcity.