diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index a65bbbc..c52c644 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-11, macos-12, macos-13]
+        os: [ubuntu-latest, macos-11, macos-12, macos-13, macos-latest-xlarge]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Set up Homebrew
@@ -36,7 +36,7 @@ jobs:
 
       - run: brew test-bot --only-tap-syntax
 
-      - run: brew test-bot --only-formulae --verbose
+      - run: brew test-bot --only-formulae --verbose --root-url=https://ghcr.io/v2/macaulay2/tap
         if: github.event_name == 'pull_request'
 
       - name: Upload bottles as artifact
diff --git a/Formula/gfan.rb b/Formula/gfan.rb
index 0a38b7b..0821fce 100644
--- a/Formula/gfan.rb
+++ b/Formula/gfan.rb
@@ -4,7 +4,7 @@ class Gfan < Formula
   url "https://users-math.au.dk/~jensen/software/gfan/gfan0.6.2.tar.gz"
   sha256 "a674d5e5dc43634397de0d55dd5da3c32bd358d05f72b73a50e62c1a1686f10a"
   license "GPL-2.0-or-later"
-  revision 10
+  revision 11
 
   bottle do
     root_url "https://github.com/Macaulay2/homebrew-tap/releases/download/gfan-0.6.2_10"