Taking to Kickstarter to update their backers, a cartoon effigy of Harmonix's Chief Creative Officer - Alex Rigopulos - has confirmed that Amplitude will be delayed until early 2016 in order to fit additional songs, environments, features, and modes into the game.
The number of songs has been pushed from 16 to 30 songs, voted on by a group of backers known as the Song Senate. The core campaign will feature 16 all-original songs written in-house by musicians and, as far as game modes are concerned, Amplitude will ship with a solo campaign, solo free play, 2-4 player 'free-for-all', and an all new team play mode.
According to Cartoon Ryan, there's also an unannounced way to play the game that will "change the way you think about Amplitude's 6-lane track".
If you backed the game on Kickstarter and received early access, you'll be able to play your reward in December on PlayStation 4. The official release date has been pushed back to January for both PlayStation 4 and PlayStation 3, albeit the latter will arrive later.