I booked a web special back in August and was able to cancel it and redeposit the miles for no fee. Probably canceled three days after I booked (well outside the 24 hour window).
This comes right off the website:
We’re waiving reinstatement fees on all AAdvantage® award travel ticketed by December 31, 2020. If your trip is eligible, your miles will be automatically reinstated within 48 hours of canceling your trip online. For all other trips, contact Reservations to have your miles reinstated.