Comment 4 for bug 1756846

That conflicts was updated in this Debian change:

diff --git a/debian/changelog b/debian/changelog
index 845b518..ecc3f29 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+bridge-utils (1.5-12) unstable; urgency=medium
+
+ * Add vlan support so that old setups using vlans as ports don't break.
+
+ -- Santiago Garcia Mantinan <email address hidden> Sun, 22 Jan 2017 00:23:50 +0100
+
 bridge-utils (1.5-11) unstable; urgency=low

   * Change /etc/default/bridge-utils to enable addition of hotplugged
diff --git a/debian/control b/debian/control
index c9b33ed..2b21fee 100644
--- a/debian/control
+++ b/debian/control
@@ -10,7 +10,7 @@ Architecture: linux-any
 Multi-Arch: foreign
 Depends: ${shlibs:Depends}, ${misc:Depends}
 Suggests: ifupdown
-Conflicts: ifupdown (<< 0.6.0)
+Conflicts: ifupdown (<< 0.8.17)
 Description: Utilities for configuring the Linux Ethernet bridge
  This package contains utilities for configuring the Linux Ethernet
  bridge in Linux. The Linux Ethernet bridge can be used for connecting
diff --git a/debian/ifupdown.sh b/debian/ifupdown.sh
index 95dac90..517f084 100644
--- a/debian/ifupdown.sh
+++ b/debian/ifupdown.sh
@@ -66,6 +66,7 @@ do
   do
     # We attach and configure each port of the bridge
     if [ "$MODE" = "start" ] && [ ! -d /sys/class/net/$IFACE/brif/$port ]; then
+ create_vlan_port
       if [ "$IF_BRIDGE_HW" ]
       then
         KVER="$(uname -r)"
@@ -84,7 +85,7 @@ do
       brctl addif $IFACE $port && ip link set dev $port up
     # We detach each port of the bridge
     elif [ "$MODE" = "stop" ] && [ -d /sys/class/net/$IFACE/brif/$port ]; then
- ip link set dev $port down && brctl delif $IFACE $port && \
+ ip link set dev $port down && brctl delif $IFACE $port && destroy_vlan_port
       if [ -f /proc/sys/net/ipv6/conf/$port/disable_ipv6 ]
       then
         echo 0 > /proc/sys/net/ipv6/conf/$port/disable_ipv6