When the COVID-19 pandemic began, nearly all productions were brought to a halt (Save those that could continue work from home or were already in post-production). Several shows cut their seasons short (Notably most of the DC shows on the CW), others improvised season finales, and others flat out delayed the rest of their current seasons until they could safely start back up again (Supernatural still has several episodes to finish for it's 15th and final season). Even with the pandemic not over, production halts have cost studios a fortune. Because of this, several safety and health procedures are being implemented so productions can restart. Several movies have already done so (Notably Jurassic World: Dominion), and now TV productions are about to follow suit.
It's been confirmed today that the CBS show S.W.A.T. is set to be the first US primetime scripted series to resume production, beginning filming this coming Tuesday in Los Angeles. Actors and crew have reportedly been tested ahead of this potential shoot. This show in particular needed to begin production again as, despite originally set to launch midseason, two weeks ago CBS announced the show would premiere in the Fall. Several shows are expected to follow this one's example with many studios planning restarts this month and into September. So far, it's been confirmed that ABC's The Good Doctor will restart in mid-August while NBC's The Blacklist and several CW shows like The Flash, Riverdale, and Supernatural will restart in late August.
It's already been confirmed by the CW that the entirety of their Arrowverse universe won't premiere their new seasons until Spring 2021 and several other shows are expected to follow this pattern. Stay tuned!