doubtful
recently i had to change a flight that i missed due to work commitments and missed the opportunity to change it over prior to flight (was out of comms)
I was able to have it changed for a very notional fee (120 dollars on a 1500 dollar flight) – the woman explained to me its because they sell on the no shows at check in closing to folk that are waiting or have been bumped from other flights due to delays.
This was KLM
What kind of flights did you book that you wont get a refund – or even credit to use on another flight ? – ive changed flights right up to an hour before flight with little issue – and i rarely fly on seamans tickets usually the cheapest of the cheap non upgradable 1/4 point earning crapfests.