diff --git a/CHANGELOG.md b/CHANGELOG.md
index c2fb85d..d7fc678 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # CHANGELOG
 
+## v2.1.0
+- Major change: deprecates websocket connection in favour of sending HTTP requests to the Upload API. In future, websocket support will be completely removed from Buildkite and only version 2.1+ of this gem will continue to work.
+
 ## v2.1.0.pre
 - Minitest plugin to use HTTP Upload API instead of websocket connection to send test data #178 #179 - @niceking
 
@@ -11,7 +14,7 @@
 
 ## v1.5.0
 
-- Send `failure_expanded` from minitest #171 - @nprizal 
+- Send `failure_expanded` from minitest #171 - @nprizal
 
 ## v1.4.2
 
diff --git a/Gemfile.lock b/Gemfile.lock
index d072ba2..61ffd73 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    buildkite-test_collector (2.1.0.pre)
+    buildkite-test_collector (2.1.0)
       activesupport (>= 4.2)
 
 GEM
diff --git a/README.md b/README.md
index 1b7c114..9ca1d37 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,8 @@
 # Buildkite Collectors for Ruby
 
+**DEPRECATION NOTICE**
+Versions prior to 2.1.x are unsupported and will not work after mid-2023. Please upgrade to the latest version.
+
 Official [Buildkite Test Analytics](https://buildkite.com/test-analytics) collectors for Ruby test frameworks ✨
 
 ⚒ **Supported test frameworks:** RSpec, Minitest, and [more coming soon](https://github.com/buildkite/test-collector-ruby/issues?q=is%3Aissue+is%3Aopen+label%3A%22test+frameworks%22).
diff --git a/lib/buildkite/test_collector/version.rb b/lib/buildkite/test_collector/version.rb
index dd64215..4231741 100644
--- a/lib/buildkite/test_collector/version.rb
+++ b/lib/buildkite/test_collector/version.rb
@@ -2,7 +2,7 @@
 
 module Buildkite
   module TestCollector
-    VERSION = "2.1.0.pre"
+    VERSION = "2.1.0"
     NAME = "buildkite-test_collector"
   end
 end
diff --git a/spec/test_collector/http_client_spec.rb b/spec/test_collector/http_client_spec.rb
index 7bef21d..e44175c 100644
--- a/spec/test_collector/http_client_spec.rb
+++ b/spec/test_collector/http_client_spec.rb
@@ -25,7 +25,7 @@
       "run_env": {
         "CI": nil,
         "key": "build-123",
-        "version": "2.1.0.pre",
+        "version": "2.1.0",
         "collector": "ruby-buildkite-test_collector",
         "test": "test_value"
       },