The first hours in the title are a framing device, not a universal shelf-life limit for market produce. Variety, harvest and ambient conditions differ; start by recording the product's journey and temperature change in your own operation.
Log purchase time, loading order, extra stops, arrival and entry to cold storage by lot. If product specifications and buyer method allow, measure the same representative sample at purchase and delivery; record the measurement point and instrument too.
Compare records to find where waiting lengthens. Trial shade, loading order, fewer extra stops or direct transfer to cold storage on a small scale. Do not calculate shelf-life loss or financial damage from one temperature difference.