The latest full stable version as of now is 2.207 (released in late 2023 / early 2024, depending on platform). Any mention of 2.208 likely comes from:
As of October 2024, Geometry Dash Update 2.208 has not been released. Furthermore, based on the official development roadmap provided by the creator, Robert Topala (RobTop), Update 2.208 is not currently planned . geometry dash 2.208 release date
Consequently, the version number (a hypothetical intermediate patch) was skipped or never utilized, and development focus has shifted directly toward the next major milestone. Version 2.208 does not currently fit into the official roadmap. The latest full stable version as of now is 2
This update brought a plethora of exciting new features, levels, and gameplay mechanics to the game, including: Robert Topala (RobTop)