HBO is confirming its “Game of Thrones” spinoff is moving forward — but don’t expect to see it on the screen anytime soon.

Ahead of HBO’s presentation at the Television Critics Association winter press tour, HBO programming president Casey Bloys told Variety that the prequel — titled “House of Dragons” and set in the days when the Targaryen dynasty ruled Westeros with the help of their dragons — isn’t expected to air until 2021.

A pilot for a different “Game of Thrones” spinoff, set thousands of years before the events of the series, was shot, but HBO execs decided not to move forward on it.

RELATED: ‘Game of Thrones’ Spinoff ‘House Of The Dragon’ Gets Series Order

“That [prequel] was 8,000 years before the current show, so it required a lot more invention,” said Bloys. “One of the benefits of ‘House of the Dragon’ is there was a text from [Game of Thrones] author George [R.R. Martin] and there was a little bit more of a roadmap. [The other prequel] did have more challenges in terms of establishing a world…”

Meanwhile, HBO’s session at the press tour yielded even more announcements, including plans for a three-part animated “Aquaman” series on the yet-to-launch streaming service HBO Max. James Wan, who directed the big-screen “Aquaman” movie, will serve as exec producer.

RELATED: ‘Aquaman’ Beats ‘Wonder Woman’ And ‘Batman v Superman’ At Box Office

“This DC property is a fan-favourite rich with well-known characters and dynamic storylines,” said Sarah Aubrey, head of original content with HBO Max. “On the heels of Warner Bros. Pictures’ box office smash hit, we are certain Aquaman: King of Atlantis will be an exciting addition to our already robust slate of kids and family programming.”

HBO Max also held its executive session on Wednesday. Among other programming, HBO Max will become the new home of “Friends” now that the beloved sitcom is no longer streaming on Netflix.

RELATED: Report: ‘Friends’ Reunion Special In The Works For HBO Max

HBO Max chief content officer Kevin Reilly was asked about reports of a potential “Friends” reunion special, but didn’t have much to report.

“There’s interest all the way around, and yet we can’t seem to quite get that interest aligned to push the button on it,” he said. “Today, unfortunately, it’s still a maybe.”

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