Doh. The article is talking about this year's Mardi Gras, but the list is referring to last year. Sorry about that. Since I'm not planning on heading to Universal until the Fall, I didn't read the article very closely. (And I can't post a link to the article as the Disboard strips the website name out of the link.)
But a closer read of the article finds the following: "Performances usually begin at 8:30 p.m. on each concert night. Concerts typically take place on select Fridays, Saturdays and Sundays throughout Universal Mardi Gras. Due to social distancing measures currently in place, there won't be scheduled concerts in 2021. Instead, you'll find roving musicians throughout the park. "
So hopefully that means no blackout dates for concerts.