Sonic the Hedgehog 2 was released on November 24, 1992 in Europe.
It was also released in Australia in 1996 as a Sega Gold Collection edition.
Sonic 2 had a release date in most Western regions which was uncommon at the time. November 24, 1992 was dubbed Sonic 2sday (a pun of the fact that it was a Tuesday), and the game was released throughout North America and the PAL territories. (It was released in Japan three days earlier.) This is referenced in the game by the order in which you need to play the sound effects to activate the debug mode.
Consoles+ No. 13 (October 1992): 92/100