EA has told Eurogamer there has been a "misunderstanding" about the Rock Band 2 date in Europe.
Word had originally pointed to a simultaneous European release alongside the US this September.
"There was a misunderstanding and there is no confirmed date for Europe," a spokesperson from EA told Eurogamer.
Rock Band 2 was unveiled yesterday and named its biggest features as the ability to carry downloadable songs between the first and second games, in addition to fresh instruments and more expansive party and online options.
The sequel will be a timed exclusive for Microsoft in the States, with other platforms due to follow later in the year.
The Q4 release puts it in direct competition with Guitar Hero World Tour, which also comes with drums, microphone, and guitar.