3GPP 21.900 v20.0.0 — the document's own text
4.10.1.2 When introducing technical changes
Taught in 3. What a Release is, and what freezing one costs (How standards actually get made, in depth).
A new version of a specification, corresponding to a new Release, shall be prepared when a technical change needs to be introduced to satisfy a requirement of a feature of that new Release. This shall be accomplished by the raising of a Change Request (see clause 4.6) in the usual way, with the version number of the resulting specification indicating the new Release. The CR shall bear the identity of the new Release (rather than the starting point Release – see clause 4.6.2).