[Firehose] Add warning for upcoming default data stream change (#3359)

docs/en/aws-firehose/aws-firehose-setup.asciidoc

@@ -43,15 +43,14 @@ In {kib}, navigate to *Management > Integrations* in the sidebar.
 Find the *AWS* integration by searching or browsing the catalog.
 
 [role="screenshot"]
-image::images/firehose-integrations-page.png[Integrations catalogue with the "AWS" integration highlighted]
+image::images/aws-integrations-page.png[Integrations catalogue with the "AWS" integration highlighted]
 
 Navigate to the *Settings* tab and click *Install AWS assets*.
 Confirm by clicking *Install AWS* in the popup. 
 
 [role="screenshot"]
 image::images/firehose-integrations-install-assets.png[AWS integration settings page with the "Install AWS assets" button highlighted]
 --
-
 . [[aws-firehose-create-delivery-stream]] Create a delivery stream in Amazon Kinesis Data Firehose.
 +
 --
@@ -103,8 +102,17 @@ A duration of 60-300s should be suitable for most use cases.
 
 * Elastic recommends setting the *`es_datastream_name`* parameter to help route data to the correct integration data streams.
 If this parameter is not specified, data is sent to the *`logs-generic-default`* data stream by default.
+
+[WARNING]
+====
+The default data stream will change to `logs-awsfirehose-default` in January 2024. *To avoid breaking changes, do not leave `es_datastream_name` empty.*
+To try the new https://docs.elastic.co/integrations/awsfirehose[routing functionality], set `es_datastream_name` to `logs-awsfirehose-default`.
+====
+
 * You can use the *`es_datastream_name`* parameter to route documents to any data stream.
-When using Elastic integrations, you must set this parameter.
+When Amazon Kinesis Data Firehose integration is installed, routing will be done automatically with `es_datastream_name` sets to `logs-awsfirehose-default`.
+When using Elastic AWS integrations without the Firehose integration, you must set this parameter to specific data streams like `logs-aws.vpcflow-default` for ingesting VPC flow logs.
+
 +
 Elastic integrations use data streams with specific naming conventions, and Firehose records need to be routed to the relevant data stream to use preconfigured index mappings, ingest pipelines, and dashboards.
 +

docs/en/aws-firehose/aws-firehose.asciidoc

@@ -6,6 +6,8 @@
 ++++
 
 {ecloud} users can ingest logs directly from AWS Kinesis Data Firehose.
+All Elastic https://www.elastic.co/integrations/data-integrations?solution=all-solutions&category=aws[AWS integrations] are supported without deploying agents to your AWS account.
+Logs from AWS Kinesis Data Firehose can be automatically routed to the relevant Elastic integration for popular AWS services with no additional configuration.
 
 AWS Kinesis Data Firehose works with {stack} version 7.17 or greater, *running on {ecloud} only*.