Season 4 is the current season of PJ Masks. It was announced on June 5, 2019. The source confirmed that they have started shooting on November 1, 2018 and ended on November 30, 2019. It was intended to be set to premiere in April 2020, but it was then moved to May 15, 2020, most likely due to the Coronavirus pandemic. It opened up with a 4-segment story arc.
The fourth season majorly focuses on the upgrades of the PJ Masks' existing vehicles, as well as the transformation of the three original villains' outfits.
News articles mentioning a PJ Masks traveling exhibit by eOne for Sea Life aquariums (which are all now closed due to the pandemic) mention that the season will also feature new underwater missions.
Currently, both the first and fourth mentioned characters have had their designs revealed at the aforementioned Toy Fair, while the official designs for the second and third mentioned characters and Octobella have yet to be revealed.
↑6 June 2019 EntertainmentOne article by Diana Veysey: "For the first time the series will open with a special 4-part episode taking PJ Masks fans on an exciting and dramatic, action-packed 44-minute adventure."