There will be more, since her psychic character from "Murder House" and "Hotel" is also set to appear. Evan Peters is also playing at least three characters: Gallant, James March (from "Hotel"), and Tate Langdon (from the first season).
Given that Michael Langdon was born in 2011, and Cody Fern is 30, they could have set this in the year 2031 and built in 13 years between "now" and the apocalypse to tell future stories in. I'm guessing the reason they went with 2020 instead is because Ryan Murphy wanted to bring the Coven...
She reminds me a lot of Meryl Streep, where everybody raves about how great of an actress she is, but when I'm watching her I can never seem to forget that I'm watching an actress giving a performance.
Previous threads:
American Horror Story [Murder House]
American Horror Story: Asylum
American Horror Story: Coven
American Horror Story: Freak Show
American Horror Story: Hotel
American Horror Story: Roanoke
If they had played it straight the way the early episodes of the first season played it...