The trade association representing air-cargo companies, such as UPS and FedEx, has written a letter to the Biden administration asking it to postpone its vaccine requirement for federal contract workers. A delay was necessary, the association said,  to avoid adding to supply-chain issues ahead of the holiday season. The letter, obtained by Politico, and addressed to Office of Management and Budget (OMB) director Shalanda Young, came from Cargo Airline Association president Stephen Alterman. It read: “We have significant concerns with the employer mandates announced on Sept. 9, 2021, and the ability of industry members to implement the required employee vaccinations by Dec. 8, 2021.” The letter went on to say it would be “virtually impossible” to fully vaccinate the hundreds of thousands of temporary workers expected to be hired during the upcoming peak shipping season and asked the White House to slide its Dec. 8 deadline for vaccines to the …