diff --git a/README.md b/README.md
index c858b47..25b5215 100644
--- a/README.md
+++ b/README.md
@@ -85,7 +85,6 @@ services:
       - PUID=1000
       - PGID=1000
       - TZ=Europe/London
-      - UMASK_SET=<022> #optional
     volumes:
       - /path/to/library:/config
       - /path/to/tvseries:/data/tvshows
@@ -114,7 +113,6 @@ docker run -d \
   -e PUID=1000 \
   -e PGID=1000 \
   -e TZ=Europe/London \
-  -e UMASK_SET=<022> `#optional` \
   -p 8096:8096 \
   -p 8920:8920 `#optional` \
   -p 7359:7359/udp `#optional` \
@@ -147,7 +145,6 @@ Container images are configured using parameters passed at runtime (such as thos
 | `-e PUID=1000` | for UserID - see below for explanation |
 | `-e PGID=1000` | for GroupID - see below for explanation |
 | `-e TZ=Europe/London` | Specify a timezone to use EG Europe/London |
-| `-e UMASK_SET=<022>` | for umask setting of Emby, default if left unset is 022. |
 | `-v /config` | Jellyfin data storage location. *This can grow very large, 50gb+ is likely for a large collection.* |
 | `-v /data/tvshows` | Media goes here. Add as many as needed e.g. `/data/movies`, `/data/tv`, etc. |
 | `-v /data/movies` | Media goes here. Add as many as needed e.g. `/data/movies`, `/data/tv`, etc. |
@@ -321,6 +318,7 @@ Once registered you can define the dockerfile to use with `-f Dockerfile.aarch64
 
 ## Versions
 
+* **20.01.21:"** - Deprecate `UMASK_SET` in favor of UMASK in baseimage, see above for more information.
 * **23.11.20:** - Rebase to Focal, branch off Bionic.
 * **22.07.20:** - Ingest releases from Jellyfin repo.
 * **28.04.20:** - Replace MMAL/OMX dependency device `/dev/vc-mem` with `/dev/vcsm` as the former was not sufficient for raspbian.
diff --git a/readme-vars.yml b/readme-vars.yml
index b5c3764..29fed33 100644
--- a/readme-vars.yml
+++ b/readme-vars.yml
@@ -35,9 +35,8 @@ param_usage_include_env: true
 param_env_vars:
   - { env_var: "TZ", env_value: "Europe/London", desc: "Specify a timezone to use EG Europe/London"}
 # optional container parameters
-opt_param_usage_include_env: true
-opt_param_env_vars:
-  - { env_var: "UMASK_SET", env_value: "<022>", desc: "for umask setting of Emby, default if left unset is 022."}
+opt_param_usage_include_env: false
+
 opt_param_usage_include_vols: true
 opt_param_volumes:
   - { vol_path: "/opt/vc/lib", vol_host_path: "/opt/vc/lib", desc: "Path for Raspberry Pi OpenMAX libs *optional*." }
@@ -114,6 +113,7 @@ app_setup_block: |
 
 # changelog
 changelogs:
+  - { date: 20.01.21:", desc: "Deprecate `UMASK_SET` in favor of UMASK in baseimage, see above for more information." }
   - { date: "23.11.20:", desc: "Rebase to Focal, branch off Bionic." }
   - { date: "22.07.20:", desc: "Ingest releases from Jellyfin repo." }
   - { date: "28.04.20:", desc: "Replace MMAL/OMX dependency device `/dev/vc-mem` with `/dev/vcsm` as the former was not sufficient for raspbian." }
diff --git a/root/etc/services.d/jellyfin/run b/root/etc/services.d/jellyfin/run
index b222572..21632b0 100644
--- a/root/etc/services.d/jellyfin/run
+++ b/root/etc/services.d/jellyfin/run
@@ -3,11 +3,12 @@
 export JELLYFIN_DATA_DIR="/config/data" \
 JELLYFIN_CONFIG_DIR="/config" \
 JELLYFIN_LOG_DIR="/config/log" \
-JELLYFIN_CACHE_DIR="/config/cache" 
+JELLYFIN_CACHE_DIR="/config/cache"
 
-# set umask
-UMASK_SET=${UMASK_SET:-022}
-umask "$UMASK_SET"
+if [ -n "${UMASK_SET}" ] && [ -z "${UMASK}" ]; then
+  echo -e "You are using a legacy method of defining umask\nplease update your environment variable from UMASK_SET to UMASK\nto keep the functionality after July 2021"
+  umask ${UMASK_SET}
+fi
 
 exec \
 	s6-setuidgid abc /usr/bin/jellyfin \