diff --git a/sandbox.mk b/sandbox.mk
index c7a6230be..c1bb28df9 100644
--- a/sandbox.mk
+++ b/sandbox.mk
@@ -103,7 +103,6 @@ deb $(MIRROR_UBUNTU_METHOD)://$(MIRROR_UBUNTU)$(MIRROR_UBUNTU_ROOT) $(MIRROR_UBU
 # MOS repos
 deb $(MIRROR_MOS_UBUNTU_METHOD)://$(MIRROR_MOS_UBUNTU)$(MIRROR_MOS_UBUNTU_ROOT) $(MIRROR_MOS_UBUNTU_SUITE) $(MIRROR_MOS_UBUNTU_SECTION)
 deb $(MIRROR_MOS_UBUNTU_METHOD)://$(MIRROR_MOS_UBUNTU)$(MIRROR_MOS_UBUNTU_ROOT) $(MIRROR_MOS_UBUNTU_SUITE)-security $(MIRROR_MOS_UBUNTU_SECTION)
-deb $(MIRROR_MOS_UBUNTU_METHOD)://$(MIRROR_MOS_UBUNTU)$(MIRROR_MOS_UBUNTU_ROOT) $(MIRROR_MOS_UBUNTU_SUITE)-proposed $(MIRROR_MOS_UBUNTU_SECTION)
 deb $(MIRROR_MOS_UBUNTU_METHOD)://$(MIRROR_MOS_UBUNTU)$(MIRROR_MOS_UBUNTU_ROOT) $(MIRROR_MOS_UBUNTU_SUITE)-updates $(MIRROR_MOS_UBUNTU_SECTION)
 deb $(MIRROR_MOS_UBUNTU_METHOD)://$(MIRROR_MOS_UBUNTU)$(MIRROR_MOS_UBUNTU_ROOT) $(MIRROR_MOS_UBUNTU_SUITE)-holdback $(MIRROR_MOS_UBUNTU_SECTION)