See https://www.irs.gov/newsroom/frequently-asked-questions-about-carrybacks-of-nols-for-taxpayers-who-h...
You waive the carryback period and calculate your NOL for 2019.
See https://www.irs.gov/publications/p536#en_US_2022_publink1000177318
Your excess becomes the carryforward to the 2020 tax year.
I will page @Mike9241 for further input.
