Recently, SEGA explained in a report from the Investor Management Conference why the new Sonic series "Sonic Frontier" was not launched in 2021 "Sonic 30th Anniversary", and said that the game will never compromise on quality.
Sega mentioned in the article: "We originally planned to launch Sonic Frontier on the 30th anniversary, but in order to further improve its quality, it was postponed. Because this is a brand new game from Sonic over the years, and we plan to launch it all platforms, we hope it will surpass its predecessor, Sonic Power, a game that will never compromise on quality."
Judging from the trailer released on the TGA, Sonic Frontier does need more polishing, and the extension may be good news. Sonic: Frontier is expected to be released during the winter holidays of 2022.