"Currently, we are offering flexible accommodations through Sunday, March 31. Due to high call volumes and extended hold times, we strongly encourage Customers to cancel, rebook, and check flight status at southwest.com. Customers who are holding reservations may rebook in the original class of service or travel standby (within 14 days of their original date of travel between the original city-pairs and in accordance with our accommodation procedures) without paying any additional charge."
Bad advice.
I booked a random flight DEN to LAS. I got the below message:
You may change your trip date/time at no additional cost if you stay inside the restrictions below.
DEPART FLIGHT RESTRICTIONS
Departure airport must be: Denver, CO - DEN
Arrival airport must be: Las Vegas, NV - LAS
Travel dates are between: 3/17/2019 to 4/14/2019
Note: Changes made outside the conditions listed above will not be protected under our established reaccommodation practices and may result in a higher fare.