Had used FF miles to purchase travel to Europe. For an inexplicable reason when I booked, the multi city function would not work so had to book two one-way trips. Out in May back in June.
Currently Alaska waives the fees for trip changes through end of May. The rep went ahead and cancelled the return without any hesitation or fees. From start to finish about 10 minutes.( including chit-chat about the weather)
EDIT/clarification- I made the reservation last Fall for travel this Spring, which obviously will not happen.