ESPN reports that Major League Baseball is currently having talks with the the Major League Baseball Players Association about pushing back the start date of spring training. This means that the 2021 season for MLB wouldn’t begin until the end of April.
This would be a bit of good news for WWE, as it was believed they would have to exit the venue prior to Wrestlemania. WWE is currently using Tropicana Field in St. Petersburg, Florida. The Tampa Bay Rays are scheduled to have their first home game against the New York Yankees there on April 9, the same weekend as Wrestlemania. So WWE would have to clear out the Thunderdome prior to that unless the schedule changes.
If Spring Training, and the 2021 season, get pushed to the end of April, that will give the company more time in the venue and more time to find a suitable replacement.