So "myself (alone) taking four UCAVs to combat" seems to suggest a single seater J-20 is UCAV command capable and integrated with what we're supposing the J-20S is supposed to do. Perhaps it's just his choice of words but maybe the J-20S has a greater capacity for this role but the J-20 has been capable of flying with loyal wingman UCAVs.
As with everything with China's military, they say it long after it's been done and become a mainstay for things as important and sensitive as this. China performs hundreds of HGV flights, China only talks about a handful. China flies J-20 with Dark Sword since 2019, China only hints this is a thing in a short video in 2021? Who knows. We have been given visual hints for some time that J-20 flies with and commands Dark Sword UCAVs.