At this moment in the trailer, it appears that this will take place during the 70s era of WandaVision. Bettany already confirmed that this series will take place over at least six different decades.
Rumors from Murphy’s Multiverse have pointed to WandaVision having as many as nine episodes going back as far as the summer of 2020, and it should amp up the excitement knowing that this is now confirmed to be true.
Disney’s official press release for Marvel Studios’ WandaVision on Dinsey+ reveals that the MCU’s debut mini-series will have nine episodes in its first season. The release reads as follows
“Featuring nine episodes, “WandaVision” kicks off on Disney+ on January 15, 2021”
This will also be interesting to see how it fits in with the recent news that the show will run premieres on Disney+ from January 15 to March 5. It seems like the first week will include a double-length episode or two episodes dropping at the same time, which should be quite the extra treat considering the MCU hasn’t released any new content since Spider-Man: Far From Home in July 2019.