Https://amtrakoig.gov/sites/default/files/webform/foia_form/_sid_/1-877-245-9984-can-i-get-a-last-minute-upgrade-with-delta-airlines-complete-guide.pdf https://amtrakoig.gov/sites/default/files/webform/foia_form/_sid_/1-877-245-9984-can-i-get-a-last-minute-upgrade-with-delta-airlines-complete-guide.pdf