The query "when is 2.21 coming out" is ambiguous without additional context, as "2.21" could refer to a software version, game update, app release, or other numbered release.
If you mean — that was released in 2010. when is 2.21 coming out
Could you clarify which software or game version 2.21 refers to? That would help give a precise release date. The query "when is 2
If you mean — Linux kernel versions jumped from 2.6.x to 3.x, so 2.21 was never released. when is 2.21 coming out
If you mean — no such version exists; the game is on 1.20+ (as of 2025).
If you meant — Blender 2.2x series is very old (early 2000s), and 2.21 would have been released around 2001–2002 if it existed.