The NBA is looking into any and every possible way for the 2019-20 season to continue despite the COVID-19 pandemic. However it appears that the 2020 NBA playoff field will remain at 16 teams with games in front of no fans.
According to Marc Berman of The New York Post, the NBA is looking at possible venues to hold a playoff series and a five-to-seven game finale to the regular season, likely in late June. Playoff series would be capped to best-of-three series, with a single elimination tournament as a last resort.
From there, the 2020-21 NBA season would theoretically begin around Christmas time.