diff --git a/Dockerfile b/Dockerfile
index 3d20968..d9ea3dc 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -47,6 +47,6 @@ CMD [ "/usr/sbin/postfix", "start-fg" ]
 # set parameters, vendor, version and build-date labels
 LABEL org.label-schema.docker.params="TZ=Etc/UTC, HOSTNAME=(container hostname), DOMAINNAME=(derived from hostname), LOCAL_ENCRYPTION=false|optional|true, SMARTHOST=..., SMARTHOST_PORT=587, SMARTHOST_USERNAME=..., SMARTHOST_PASSWORD=..., SMARTHOST_ENCRYPTION=optional|false|true"
 LABEL org.label-schema.vendor="Alpine 3.13, Postfix 3.5.10-r0"
-LABEL org.label-schema.version="0.9"
+LABEL org.label-schema.version="1.0"
 ARG BUILD_DATE
 LABEL org.label-schema.build-date=${BUILD_DATE}