Final answer:
The release date for Stranger Things season 4 has not been officially announced yet. Filming started in 2020 and it is expected to premiere in late 2021 or early 2022.
Step-by-step explanation:
The release date for Stranger Things season 4 has not been officially announced yet. However, filming for the season started in early 2020, but was temporarily halted due to the COVID-19 pandemic. It is expected to premiere in late 2021 or early 2022, but this is subject to change.