[VSA] Announce deprecation of VSA filtering calculation

data/deprecations/14-5-deprecation-vsa-announce-deprecation-of-vsa-filtering-calculation.yml

+- name: "Value Stream Analytics filtering calculation change" # The name of the feature to be deprecated
+  announcement_milestone: "14.5" # The milestone when this feature was first announced as deprecated.
+  announcement_date: "2021-11-22" # The date of the milestone release when this feature was first announced as deprecated. This should almost always be the 22nd of a month (YYYY-MM-22), unless you did an out of band blog post.
+  removal_milestone: "15.0" # The milestone when this feature is planned to be removed
+  body: | # Do not modify this line, instead modify the lines below.
+    We are changing how the date filter works in Value Stream Analytics. Instead of filtering by the time that the issue or merge request was created, the date filter will filter by the end event time of the given stage. This will result in completely different figures after this change has rolled out. 
+    
+    If you monitor Value Stream Analytics metrics and rely on the date filter, to avoid losing data, you must save the data prior to this change.
+  stage: manage # (optional - may be required in the future) String value of the stage that the feature was created in. e.g., Growth
+  tiers: # (optional - may be required in the future) An array of tiers that the feature is available in currently.  e.g., [Free, Silver, Gold, Core, Premium, Ultimate]
+  issue_url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/343210' # (optional) This is a link to the deprecation issue in GitLab
+  documentation_url: "https://docs.gitlab.com/ee/user/analytics/value_stream_analytics.html#filter-value-stream-analytics-data" # (optional) This is a link to the current documentation page
+  image_url: "vsa_warning.png" # (optional) This is a link to a thumbnail image depicting the feature

doc/update/deprecations.md

@@ -157,6 +157,14 @@ In milestone 15.0, we will remove the feature flag entirely. Moving forward, you
 
 Announced: 2021-11-22
 
+### Value Stream Analytics filtering calculation change
+
+We are changing how the date filter works in Value Stream Analytics. Instead of filtering by the time that the issue or merge request was created, the date filter will filter by the end event time of the given stage. This will result in completely different figures after this change has rolled out. 
+
+If you monitor Value Stream Analytics metrics and rely on the date filter, to avoid losing data, you must save the data prior to this change.
+
+Announced: 2021-11-22
+
 ### `AuthenticationType` for `[runners.cache.s3]` must be explicitly assigned
 
 In GitLab 15.0 and later, to access the AWS S3 cache, you must specify the `AuthenticationType` for [`[runners.cache.s3]`](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-runnerscaches3-section). The `AuthenticationType` must be `IAM` or `credentials`.