What can I do?

Hi everyone, I was scheduled to go on a trip to Scotland next week, but just found out that a spot opened up in the August cohort of a graduate program I was scheduled to start in December which will now begin during my trip.

My flight from EWR to GLA class is United Economy L (Cost $295) and the return is class United Economy XN (Cost 36k miles and $183 in taxes/fees). These were purchased using my United credit card and miles transferred from my Chase Sapphire account.

I did not purchase travel insurance (will do in the future) on these flights, so I can pay a $149/ticket cancellation fee, but would ideally like to avoid that. Is there ANYTHING I can do to either cancel, refund, or credit these tickets back to me without that fee, either thru United or Chase?

TIA