Regulations regarding Drosophila melanogaster importation and interstate movement were revised in 2020 and the USDA transitioned to new documentation in April 2021. Under the old rules, almost all transgenic strains were imported under Courtesy Permits, which were issued on a country-by-country basis and expired after three years. They were issued with a Letter of No Jurisdiction, which explained USDA rules to customs officials. The documents together allowed shipments to pass through border inspections and be sent directly to you.
We are strongly encouraging everyone to apply for the new import documents and to abandon the old documents quickly. The new system is simpler in most respects. Nevertheless, the old documents may be used in the way they were intended until they expire.
Do not substitute an old Letter of No Jurisdiction for a Letter of No Permit Required under the new rules. The documents are not equivalent.