When is a 13-year discrepancy immaterial?

According to the UK ASA, when it's the difference between 1860 and 1873 as the confirmed date of a bakery's founding: "We understood that their competitors were much younger, with the oldest having been founded in 1949 and so Warrens Bakery was the oldest pasty provider still trading. In light of that, we considered that any consumers who had chosen to purchase a pasty from Warrens Bakery, as opposed to one of their competitors, because of their claimed heritage, would still have made the same decision to do so had they been aware that the earliest official record of the bakery's existence that they were able to supply was 1873."