diff --git a/CHANGELOG.md b/CHANGELOG.md
index add8d271..9ae43860 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,8 +7,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+### Changed
+
+### Hardware
+
+
+## [26.8.21]
+
 ### Added
 - Added new BLE firmware update protocol.
+- Updated build script.
 
 ### Changed
 - Truncate only the BLE-advertised device name when needed so the SmartSpin2k service UUID remains present in the legacy scan response.
diff --git a/include/cert.h b/include/cert.h
index 4fec8260..53645c33 100644
--- a/include/cert.h
+++ b/include/cert.h
@@ -7,13 +7,13 @@
 
 /*
  * Automatically updated CA certificate for raw.githubusercontent.com
- * Last updated: 2026-04-05 08:58:47
+ * Last updated: 2026-08-23 08:57:32
  */
 
 #pragma once
 
 // certificate for https://raw.githubusercontent.com
-// Let's Encrypt R12, valid until Thu May 07 2026, size: 1934 bytes
+// Let's Encrypt YR1, valid until Sat Oct 31 2026, size: 1934 bytes
 const char* rootCACertificate =
     "-----BEGIN CERTIFICATE-----\n"
     "MIIFazCCA1OgAwIBAgIRAIIQz7DSQONZRGPgu2OCiwAwDQYJKoZIhvcNAQELBQAwTzELMAkGA1UE\n"
diff --git a/platformio.ini b/platformio.ini
index 7cee719b..4ace3a0c 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -48,9 +48,9 @@ custom_component_remove =
     espressif/rmaker_common
     espressif/lan867x
 build_flags =
-    !python git_tag_macro.py
-    !python build_date_macro.py
-    !python cert_updater.py
+    !python3 git_tag_macro.py
+    !python3 build_date_macro.py
+    !python3 cert_updater.py
     ;-DCONFIG_FREERTOS_PLACE_FUNCTIONS_INTO_FLASH=y
     ;-D CONFIG_SPI_SLAVE_ISR_IN_IRAM=n
     ;-D CONFIG_NEWLIB_NANO_FORMAT=y