diff --git a/update.sh b/update.sh
index cd73b6e22..88dcec115 100755
--- a/update.sh
+++ b/update.sh
@@ -66,7 +66,6 @@ fi
 arch=$(get_arch)
 
 if [ "${SKIP}" != true ]; then
-  alpine_version=$(get_config "./" "alpine_version")
   yarnVersion="$(curl -sSL --compressed https://yarnpkg.com/latest-version)"
 fi
 
@@ -135,9 +134,6 @@ function update_node_version() {
     sed -Ei -e 's/^FROM (.*)/FROM '"$fromprefix"'\1/' "${dockerfile}-tmp"
     sed -Ei -e 's/^(ENV NODE_VERSION ).*/\1'"${nodeVersion}"'/' "${dockerfile}-tmp"
 
-    currentYarnVersion="$(grep "ENV YARN_VERSION" "${dockerfile}" | cut -d' ' -f3)"
-    sed -Ei -e 's/^(ENV YARN_VERSION ).*/\1'"${currentYarnVersion}"'/' "${dockerfile}-tmp"
-
     # shellcheck disable=SC1004
     new_line=' \\\
 '
@@ -172,11 +168,9 @@ function update_node_version() {
     if diff -q "${dockerfile}-tmp" "${dockerfile}" > /dev/null; then
       echo "${dockerfile} is already up to date!"
     else
-      if [ "${SKIP}" = true ]; then
-        # Get the currently used Yarn version
-        yarnVersion="$(grep "ENV YARN_VERSION" "${dockerfile}" | cut -d' ' -f3)"
+      if [ "${SKIP}" != true ]; then
+        sed -Ei -e 's/^(ENV YARN_VERSION ).*/\1'"${yarnVersion}"'/' "${dockerfile}-tmp"
       fi
-      sed -Ei -e 's/^(ENV YARN_VERSION ).*/\1'"${yarnVersion}"'/' "${dockerfile}-tmp"
       echo "${dockerfile} updated!"
     fi