I have a credit with TA which was for travel last month to Istanbul and Budapest.
Due to covid-19 the flights were canceled and my ticket was made an open ticket or credit (they called it an open ticket-no cash refund) which I have to use by February 2021 (last flight has to be the last day of Feb).
On checking their website today, I see they have now extended the expiration to December 2021.
This is good news for those of us with credit on TA who do not want to travel (if possible) anywhere this year.
If I read the terms correctly, there is no change fee and no fare difference to be charged when rebooking unless you change the class of service.