He said during the last year before they were liberated, the Red Cross deliveries from Switzerland stopped as a result of the Russian advance. My question is since Switzerland was neutral and supposedly these deliveries were untouchable, why would the Russian advance cause them to stop?
He said after four months they started getting new deliveries from Sweden.
If it matters he was in a camp near the Baltic sea, one that supposedly only for airmen.
More likely this was due to transport issues within Germany; rather than Switzerland stopping the deliveries because of the Soviet advance.
While the deliveries were protected by international law, Germany was not obliged to make all effort to have these supplies delivered. Indeed by 1945 the Soviet army had advanced deep into Hungary and was pounding on the gates of Budapest, so it would not be out of the question for the Germans to stop caring about Red Cross packages in favor of keeping their troops supplied in the South.
That the source of shipments instead switched to the north from Sweden - which would go through Denmark that was mostly unaffected by the war even at this point - likely confirms that this was a German transport issue instead of a Russian "advance" problem.