release-flow: Extend support period 3 months after last release

Clarify that support is provided even after the the last point release
is published and that the overall support period is two years from the
`.0` release.

Signed-off-by: Emanuele Aina <emanuele.aina@collabora.com>

content/policies/release-flow.md

@@ -398,11 +398,21 @@ later point release. This means the initial product release for 2020 would be
 After a release has been done, for each of them there is an expected support
 life depending on the type of release as outlined above.
 
-For non-product release any post-release updates will directly go into the main
-repository for that specific release. For product releases a setup similar to
+For non-product releases any post-release updates will directly go into the main
+repository for that specific release. Only fixes to high-impact issues will be
+published for non-product releases, everything else will only be available in
+the next release.
+
+For product releases a setup similar to
 Debian is to be used to stage updates before a new point release is done. The
 repositories used by Apertis are outlined in the following sections.
 
+Point releases are published every quarter and when this happens the staged
+updates get folded in the main repository. The last point release is a special
+case since after three months the staged updates will get folded but no
+additional point release is published. The overall support period of a product
+release is thus two years from the `.0` release.
+
 ### Stable Repository
 
 This is the main repository with the full *released* version. This repository
@@ -416,6 +426,9 @@ For instance, in Apertis v2021 this maps to:
 * the `apertis:v2021:{target,development,sdk,hmi}` OBS repositories
 * the `deb https://repositories.apertis.org/apertis/ v2021 target development sdk hmi` APT source
 
+Once a point release is published, the updates staged in the repositories
+described below get folded in this repository to make them generally available.
+
 ### Security repository
 
 For security issues a dedicated security repository is used. This repository
@@ -511,6 +524,7 @@ looks like this:
 | 2022Q2  | Apertis 2021.5             | v2021.5   |  stable point release     |
 | 2022Q3  | Apertis 2021.6             | v2021.6   |  stable point release     |
 | 2022Q4  | Apertis 2021.7             | v2021.7   |  stable point release     |
+| 2023Q1  |                            |           |  end of support for v2021 |
 
 For projects using Apertis (or its direct downstreams) given this schedule there is a rebase window
 of a year to move to the newer version. Starting from when the preview release