I purchased 5 round-trip flights on 6/20/20. I used $600 in vouchers and charged $281 to my Aspire Amex. (Frontier was already selected as my airline of choice from 2019.)
Didn't check it for 3 days...Checked today, 6/23/20, and the charge has posted, no credit yet, but my meter shows that I've used my full credit for the year. Yay!
This again was straight airfare, taxes, and fees since I'm an Elite50K with Frontier and don't pay for seat assignments or luggage. I was already a Discount Den member.
ETA: The roundtrip fares were $119 each and the kids fly free promo applied to two tickets on the return flight only. (2 adults, 3 kids)