Just guessing, but given the probable circumstances, would that mean cashing advance for fuel, air nav charges, terminal fees, cleaning and handling and a whole heap of other stuff?
I’d say very likely, a stable credit worthy airline with a good payment record will get a bill once a month. Once the finances start looking shaky it’s COD before anything moves and news travels fast. Expect to see delays while the airline adapts to the new order of paying for everything n advance.