3GPP 21.900 v20.0.0 — the document's own text
4.10.1.1 With no technical changes compared to the previous Release
Taught in 3. What a Release is, and what freezing one costs (How standards actually get made, in depth).
A given Release consists of a set of specifications having a common "major" version field; therefore, for the set of specifications to be complete, a new specification needs to be produced even if its provisions are identical with those of the previous Release's version. The creation of such a specification shall be delayed until the latest possible moment - that is, until the TSG is on the point of declaring a given Release to be complete, having determined that no technical changes are needed in the specification compared with the previous Release.
The creation of the new version under these circumstances shall be via the responsible TSG's taking a decision to upgrade to the next Release of the specification.
This implies that all Groups need to conduct a rigorous review of all specifications for which they are responsible to determine which are to be propagated to the next Release and which are not.