Welcome to FT!, All4naught1
Understand your frustration, my daughter had tickets on a non-USA carrier (PA) purchase via Expedia and it took 7 months to get a refund. Fortunately she had a letter from the airline / Expedia announcing the cancellation.
Appears these are all AC flights, have you contacted AC for documentation? UA has a method to provide document of delays and irrops cancellations (for trip insurance) for its flights. Best to deal with the operating airline.
Perhaps this is better placed in the AC forum. use the red triangle symbol to request a move.
Update: Moved to AC from UA forum per OP request,
Last edited by WineCountryUA; Mar 29, 2021 at 7:42 pm
Reason: Update