On July 14, 2023, I booked a $74.90 flight using $50 IHG United Travelbank funds with expiry date 7/15/23 and $24.90 IHG United Travelbank funds with expiry date 1/15/24.

The aforementioned flight scheduled to depart this October is now cancelled. Under "schedule change", I see that I already got put on a different flight. In this case, what are my options?
Are they able to refund back to my travelbank funds with a new, extended expiry date? If so, what new expiry date shall I expect?
Am I able to request refund in United miles in lieu of getting travelbank funds?