diff --git a/.changeset/fix-main-beta3-merge.md b/.changeset/fix-main-beta3-merge.md
new file mode 100644
index 000000000..feebf3c9b
--- /dev/null
+++ b/.changeset/fix-main-beta3-merge.md
@@ -0,0 +1,4 @@
+---
+---
+
+CI and test only: the packed-size budgets and a stale 3.3.0-beta.2 test pin after #3559, #3560 and #3564 landed together.
diff --git a/scripts/check-package-size.mjs b/scripts/check-package-size.mjs
index 6e54bcbc9..05bb1a9f4 100644
--- a/scripts/check-package-size.mjs
+++ b/scripts/check-package-size.mjs
@@ -166,7 +166,10 @@ import { assertPublishProtocolArtifacts } from './check-publish-protocol-artifac
 // ones (the composed protocol envelope on every response, live creative updates, the
 // reporting_subscription_probe controller scenario) and regenerates the types. Measured
 // 26,825,751 packed bytes; allow about 44 KB above that. Other budgets stay fixed.
-const MAX_PACKED_TARBALL_BYTES = 26_870_000;
+// The beta.3 engine slice (#3560) and the creative package-fit decisions (#3564) landed together on
+// main: 26,862,555 packed bytes. Allow about 45 KB above that, which also covers the release PR's
+// CHANGELOG growth.
+const MAX_PACKED_TARBALL_BYTES = 26_910_000;
 const MAX_UNPACKED_PACKAGE_BYTES = 144 * 1024 * 1024;
 // AdCP 3.2.0-beta.10 adds the account-change schema family. The seller reporting
 // ledger adds ten public module artifacts. AdCP 3.2.0-rc.2 replaced the preview
@@ -345,7 +348,8 @@ const MAX_PACKED_FILE_COUNT =
   3 + // Reporting-subscription seller and buyer guides, and the reporting-subscriptions skill.
   // AdCP 3.3.0-beta.3: eleven new source schemas (task-id, task-message and the task-status envelopes; live
   // creative updates) and the new compliance storyboards and controller-scenario files that ship with them.
-  21;
+  21 + // AdCP 3.3.0-beta.3 adoption (#3559).
+  1; // Creative package-fit guide (#3564), merged in parallel with #3559's exact count.
 const MAX_BUNDLED_SCHEMA_BYTES = 2000 * 1024;
 const MAX_CJS_SCHEMA_DECLARATION_BYTES = 45 * 1024 * 1024;
 const MAX_ESM_SCHEMA_FACADE_BYTES = 1024;
diff --git a/test/lib/creative-package-fit.test.js b/test/lib/creative-package-fit.test.js
index b43bfcd0c..20439448d 100644
--- a/test/lib/creative-package-fit.test.js
+++ b/test/lib/creative-package-fit.test.js
@@ -504,10 +504,11 @@ test('non-default legacy density is retained or refused, never silently discarde
   assert.ok(!shared.wire || shared.wire.selector.format_id.pixel_ratio === 2);
 });
 test('sync snapshots measured creative facts before capability discovery', async () => {
-  const { SingleAgentClient } = require('../../dist/lib');
+  const { SingleAgentClient, ADCP_VERSION } = require('../../dist/lib');
+  // The SDK's own 3.3 preview pin: only the current beta bundle ships.
   const client = new SingleAgentClient(
     { id: 'fit-seller', name: 'Acme seller', protocol: 'mcp', agent_uri: 'https://seller.acme.example/mcp' },
-    { adcpVersion: '3.3.0-beta.2', validation: { requests: 'off', responses: 'off' } }
+    { adcpVersion: ADCP_VERSION, validation: { requests: 'off', responses: 'off' } }
   );
   const creative = image();
   const packages = [pkg('A', declaration({ width: 300, height: 250 }))];