diff --git a/support/testing/tests/boot/test_edk2.py b/support/testing/tests/boot/test_edk2.py
index e6b7855284..39d7a4dbcc 100644
--- a/support/testing/tests/boot/test_edk2.py
+++ b/support/testing/tests/boot/test_edk2.py
@@ -35,6 +35,28 @@ class TestEdk2(infra.basetest.BRTest):
         BR2_PACKAGE_HOST_QEMU_SYSTEM_MODE=y
         """
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestEdk2, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestEdk2.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         hda = os.path.join(self.builddir, "images", "disk.img")
         flash0 = os.path.join(self.builddir, "images", "SBSA_FLASH0.fd")
diff --git a/support/testing/tests/boot/test_grub.py b/support/testing/tests/boot/test_grub.py
index c753a16c34..c6e86f7b71 100644
--- a/support/testing/tests/boot/test_grub.py
+++ b/support/testing/tests/boot/test_grub.py
@@ -58,6 +58,28 @@ class TestGrubi386EFI(infra.basetest.BRTest):
         BR2_PACKAGE_HOST_DOSFSTOOLS=y
         """.format(infra.filepath("tests/boot/test_grub/post-build.sh"))
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestGrubi386EFI, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestGrubi386EFI.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         hda = os.path.join(self.builddir, "images", "disk.img")
         bios = os.path.join(self.builddir, "images", "OVMF.fd")
@@ -109,6 +131,28 @@ class TestGrubX8664EFI(infra.basetest.BRTest):
         BR2_PACKAGE_HOST_DOSFSTOOLS=y
         """.format(infra.filepath("tests/boot/test_grub/post-build.sh"))
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestGrubX8664EFI, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestGrubX8664EFI.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         hda = os.path.join(self.builddir, "images", "disk.img")
         bios = os.path.join(self.builddir, "images", "OVMF.fd")
@@ -158,6 +202,28 @@ class TestGrubAArch64EFI(infra.basetest.BRTest):
         """.format(post_image=infra.filepath("tests/boot/test_grub/post-image-aarch64-efi.sh"),
                    linux_fragment=infra.filepath("tests/boot/test_grub/linux-aarch64-efi.config"))
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestGrubAArch64EFI, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestGrubAArch64EFI.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         hda = os.path.join(self.builddir, "images", "disk.img")
         bios = os.path.join(self.builddir, "images", "QEMU_EFI.fd")
diff --git a/support/testing/tests/fs/test_iso9660.py b/support/testing/tests/fs/test_iso9660.py
index 3d08f2e895..6f8ca06de3 100644
--- a/support/testing/tests/fs/test_iso9660.py
+++ b/support/testing/tests/fs/test_iso9660.py
@@ -135,6 +135,28 @@ class TestIso9660Grub2EFI(infra.basetest.BRTest):
         """.format(infra.filepath("conf/grub2-efi.cfg"),
                    infra.filepath("conf/grub2.cfg"))
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestIso9660Grub2EFI, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestIso9660Grub2EFI.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         exit_code = test_mount_internal_external(self.emulator,
                                                  self.builddir, internal=True,
@@ -163,6 +185,28 @@ class TestIso9660Grub2Hybrid(infra.basetest.BRTest):
         """.format(infra.filepath("conf/grub2-efi.cfg"),
                    infra.filepath("conf/grub2.cfg"))
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestIso9660Grub2Hybrid, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestIso9660Grub2Hybrid.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         exit_code = test_mount_internal_external(self.emulator,
                                                  self.builddir, internal=True,
diff --git a/support/testing/tests/package/test_fwts.py b/support/testing/tests/package/test_fwts.py
index 5b79a17e33..6e2b6f50ba 100644
--- a/support/testing/tests/package/test_fwts.py
+++ b/support/testing/tests/package/test_fwts.py
@@ -38,6 +38,28 @@ class TestFwts(infra.basetest.BRTest):
         BR2_PACKAGE_HOST_QEMU_SYSTEM_MODE=y
         """
 
+    def __init__(self, names):
+        """Setup common test variables."""
+        super(TestFwts, self).__init__(names)
+        """All EDK2 releases <= edk2-stable202408 can't be fetched from git
+           anymore due to a missing git submodule as reported by [1].
+
+           Usually Buildroot fall-back using https://sources.buildroot.net
+           thanks to BR2_BACKUP_SITE where a backup of the generated archive
+           is available. But the BRConfigTest remove BR2_BACKUP_SITE default
+           value while generating the .config used by TestFwts.
+
+           Replace the BR2_BACKUP_SITE override from BRConfigTest in order
+           to continue testing EDK2 package using the usual backup site.
+
+           To be removed with the next EDK2 version bump using this commit
+           [2].
+
+           [1] https://github.com/tianocore/edk2/issues/6398
+           [2] https://github.com/tianocore/edk2/commit/95d8a1c255cfb8e063d679930d08ca6426eb5701
+        """
+        self.config = self.config.replace('BR2_BACKUP_SITE=""\n', '')
+
     def test_run(self):
         hda = os.path.join(self.builddir, "images", "disk.img")
         flash0 = os.path.join(self.builddir, "images", "SBSA_FLASH0.fd")