update on my own efforts, purchased 3 day passes via United app (as a single transaction) on 12/27, transaction posted as 3 individual charges. reimbursements posted on 12/30. processed three more purchases on a separate Amex Biz Plat card on 12/30... I hope those credits will be taken out of 2019 $200 balance... (likely to post on 01/02)...?