House of the Dragon officially began production in April of last year with an official release date for its debut season coming nearly one year later. The show ultimately premiered in August to much critical acclaim and an immediate renewal for a second season (and, quite possibly, a third one). But, more importantly, the timeline from the start of production and when the show came out comes out to roughly around 16 months. If we believe the words of Ewan Mitchell, Aemond Targaryen's actor, this suggests that House of the Dragon Season 2 won't arrive until much later in 2024 if not early 2025.
In a lengthy interview with The Face, Mitchell talks a lot about his character in House of the Dragon and what it was like to film the show. Later on, Mitchell reveals that the show's cast and crew will spend eight months next year filming the second season.
An earlier report claims that House of the Dragon Season 2 will start filming early next year. Based on what Mitchell just said, filming won't wrap up until the tail end of the year and it might even last until 2024. When you add in post-production, potential reshoots, and the extensive CGI work (we're expecting to see more dragons next season), then the return of House of the Dragon won't be anytime soon.
If it's any consolation, George R.R. Martin has openly said he wants House of the Dragon to last for four full seasons, which implies that the show will be around for much of the current decade. The showrunners haven't confirmed how long House of the Dragon will run yet, but we're pretty sure they'll do a better job at listening to the source material's author unlike the co-creators of Game of Thrones, Daniel Brett Weiss and David Benioff.
TLDR; House of the Dragon Season 2 definitely won't premiere next year, as much as Ryan Condal would like you to believe otherwise.