Hi Julián!
As Kashif77 mentioned, Maintenance builds are final releases for that sub version. In your example, that means that there should not be an officially released 16.02.xxxx build after that (except for extremely critical fixes).
This is useful for customers that will not update or require new features to upgrade for, as well as for companies that have strict code change policies. These customers can rely on the stability of the dependable maintenance version.
In most cases, however, the general bug fixes that are added into the 16.02 builds are rolled into the 16.03 builds and the proceeding builds thereafter, so later builds will have the bug fixes in addition to newer features and releases. That is to say that if there are functionalities that you intend to use in later releases, there shouldn't be open bugs fom previous versions.