BF upgrade question
 

Excuse me if this question is so rudimentary or answer so obvious but what happens if one buys a refundable H fare and successfully upgrades to BF with miles and a fee and then later changes the flight and the new flight has no BF availability or cancels flight altogether. Does one get a refund of the miles and fee?

Thanks

You can refund the miles, but not the fee. There is no fee for full Y.

You should get the fee back if you reschedule. You waitlist for the new flight (since theres no seats left for an upgrade) and then when the upgrade doesn't clear you get your miles and money back.

The wording on the CO website is slightly ambiguous with regard to whether the BF service fee is refundable for "H" fares.
Generally, it is completely nonrefundable if you make any involntary changes and cannot re-confirm the upgrade, and my interpretation is that this holds true for H fares as well.