diff --git a/.github/workflows/build-swift-nightly.yml b/.github/workflows/build-swift-nightly.yml
index eafc69a..00ebb5a 100644
--- a/.github/workflows/build-swift-nightly.yml
+++ b/.github/workflows/build-swift-nightly.yml
@@ -3,7 +3,7 @@ name: Build Swift Nightly
 on:
   pull_request:
   schedule:
-    - cron: '0 21 * * *'
+    - cron: '0 9 * * *'
 
 env:
   DISTRIBUTION: debian-bookworm
diff --git a/swift-builder/Dockerfile b/swift-builder/Dockerfile
index 5170f52..d5a356e 100644
--- a/swift-builder/Dockerfile
+++ b/swift-builder/Dockerfile
@@ -44,8 +44,7 @@ ARG SWIFT_BRANCH=development
 ARG SWIFT_VERSION=swift-DEVELOPMENT-SNAPSHOT-2024-12-13-a
 ARG SWIFT_WEBROOT=https://download.swift.org
 
-ENV SWIFT_SIGNING_KEY=$SWIFT_SIGNING_KEY \
-    SWIFT_PLATFORM=$SWIFT_PLATFORM \
+ENV SWIFT_PLATFORM=$SWIFT_PLATFORM \
     SWIFT_BRANCH=$SWIFT_BRANCH \
     SWIFT_VERSION=$SWIFT_VERSION \
     SWIFT_WEBROOT=$SWIFT_WEBROOT