system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If principle photography is done AND a teaser trailer is out, why wont the new Star Wars be in theaters until next December?
gpt
Post Production.  This is when all of the CGI, sound mixing, editing, scoring and much much more is done.

Additionally,  they're  will probably be reshoots. Therefore, the one year gap gives them plenty of cushion time.