-echo -e "deb [arch="${DOCKER_ARCH}"] "${DOCKER_REPO}" xenial-updates universe
-deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" trusty main universe multiverse restricted
-deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" trusty-updates main universe multiverse restricted
-deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" trusty-security main universe multiverse restricted
-deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" trusty-proposed main universe multiverse restricted" > "${sub_source_file}"
+if [[ "${VERSION_CODENAME}" != "xenial" ]]; then
+ REPO_UPDATE="deb [arch="${DOCKER_ARCH}"] "${DOCKER_REPO}" xenial-updates universe"
+fi
+
+echo -e ""${REPO_UPDATE}"
+deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" "${VERSION_CODENAME}" main universe multiverse restricted
+deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" "${VERSION_CODENAME}"-updates main universe multiverse restricted
+deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" "${VERSION_CODENAME}"-security main universe multiverse restricted
+deb [arch="${EXTRA_ARCH}"] "${EXTRA_REPO}" "${VERSION_CODENAME}"-proposed main universe multiverse restricted" > "${sub_source_file}"