For 1. That would be because the FDA insisted on a US run phase 3 trial (which is fine) but that only began around the time the UK approved Oxford/AZ as AZ had

For 1. That would be because the FDA insisted on a US run phase 3 trial (which is fine) but that only began around the time the UK approved Oxford/AZ as AZ had first tried to use their UK/SA study for US approvals