HBO chief executive Casey Bloys recently spoke at the Television Critics Association’s Press Tour and revealed that the network does not wish to draw any attention away from the final season of Game of Thrones and therefore, will not release any spinoff/prequel until at least a year after the series finale:
“The No. 1 priority in all of this is the final season of Game of Thrones. I don’t want to do anything with a spin-off or anything that detracts or distracts from that. That season will happen and my guess is it would be at least a year before you saw anything else. What I don’t want is the attention to be drawn from the final season, which I think is going to be epic and amazing and somehow have the distraction of a new Game of Thrones airing right after that. It’s best to separate it and that’s what we’ll do.”
As announced previously, HBO is currently developing four prequels with Game of Thrones/A Song of Ice & Fire author George R.R. Martin attached to all of them. Bloys also confirmed that none of characters from Game of Thrones will feature in these projects.