diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..70c57bd
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,9 @@
+# export $(grep -v '^#' .env | xargs)
+
+SOURCE_HOST=
+SOURCE_ORG=
+GH_SOURCE_PAT=
+
+TARGET_HOST=
+TARGET_ORG=
+GH_TARGET_PAT=
diff --git a/.gitignore b/.gitignore
index d52ace2..a465620 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,6 @@
 node_modules*
 test*.js
 test*.sh
+temp
+tool
+.env
diff --git a/scripts/migrate-npm-packages-between-github-instances.sh b/scripts/migrate-npm-packages-between-github-instances.sh
index 4fbcdd5..f774acf 100755
--- a/scripts/migrate-npm-packages-between-github-instances.sh
+++ b/scripts/migrate-npm-packages-between-github-instances.sh
@@ -11,27 +11,27 @@
 # Example: ./migrate-npm-packages-between-github-instances.sh joshjohanning-org github.com joshjohanning-emu github.com | tee output.log
 #
 # Notes:
-# - Mapping the npm package to a repo is optional. 
+# - Mapping the npm package to a repo is optional.
 #   - If there is a repo that exists in the target with the same repo name, it will map it
 #   - If the repo doesn't exist, the package will still import but won't be mapped to a repo
 # - See ./failed-packages.txt for any packages that failed to import
 
 set -e
 
-if [ $# -ne "4" ]; then
-    echo "Usage: $0 <source-org> <source-host> <target-org> <target-host>"
-    exit 1
+if [ $# -lt "4" ]; then
+  echo "Usage: $0 <source-org> <source-host> <target-org> <target-host>"
+  exit 1
 fi
 
 # make sure env variables are defined
 if [ -z "$GH_SOURCE_PAT" ]; then
-    echo "Error: set GH_SOURCE_PAT env var"
-    exit 1
+  echo "Error: set GH_SOURCE_PAT env var"
+  exit 1
 fi
 
 if [ -z "$GH_TARGET_PAT" ]; then
-    echo "Error: set GH_TARGET_PAT env var"
-    exit 1
+  echo "Error: set GH_TARGET_PAT env var"
+  exit 1
 fi
 
 echo "..."
@@ -40,6 +40,11 @@ SOURCE_ORG=$1
 SOURCE_HOST=$2
 TARGET_ORG=$3
 TARGET_HOST=$4
+# Optional: Set CUTOFF_DATE to migrate only package versions created on or after this date.
+# Format: YYYY-MM-DDTHH:MM:SSZ (e.g., 2023-03-13T00:00:00Z)
+# Example: To migrate versions from the past year, use: $(date -u -v-1y +"%Y-%m-%dT%H:%M:%SZ")
+# If CUTOFF_DATE is unset or empty, all available versions will be migrated.
+CUTOFF_DATE=$5
 
 # create temp dir
 mkdir -p ./temp
@@ -47,7 +52,7 @@ cd ./temp
 temp_dir=$(pwd)
 
 # set up .npmrc for target org
-echo @$TARGET_ORG:registry=https://npm.pkg.$TARGET_HOST/ > $temp_dir/.npmrc && echo "//npm.pkg.$TARGET_HOST/:_authToken=$GH_TARGET_PAT" >> $temp_dir/.npmrc
+echo @$TARGET_ORG:registry=https://npm.pkg.$TARGET_HOST/ >$temp_dir/.npmrc && echo "//npm.pkg.$TARGET_HOST/:_authToken=$GH_TARGET_PAT" >>$temp_dir/.npmrc
 
 packages=$(GH_HOST="$SOURCE_HOST" GH_TOKEN=$GH_SOURCE_PAT gh api --paginate "/orgs/$SOURCE_ORG/packages?package_type=npm" -q '.[] | .name + " " + .repository.name')
 
@@ -57,32 +62,44 @@ echo "$packages" | while IFS= read -r response; do
   repo_name=$(echo "$response" | cut -d ' ' -f 2)
 
   echo "org: $SOURCE_ORG repo: $repo_name --> package name $package_name"
-  
-  versions=$(GH_HOST="$SOURCE_HOST" GH_TOKEN=$GH_SOURCE_PAT gh api --paginate "/orgs/$SOURCE_ORG/packages/npm/$package_name/versions" -q '.[] | .name' | sort -V)
-  for version in $versions
-  do
+
+  # Cache package metadata to avoid multiple API calls for each version
+  curl -H "Authorization: token $GH_SOURCE_PAT" -Ls "https://npm.pkg.github.com/@$SOURCE_ORG/$package_name" >"${temp_dir}/${package_name}.json"
+
+  # Fetch versions, filter by date only if CUTOFF_DATE is set
+  if [ -n "$CUTOFF_DATE" ]; then
+    versions=$(GH_HOST="$SOURCE_HOST" GH_TOKEN=$GH_SOURCE_PAT gh api --paginate "/orgs/$SOURCE_ORG/packages/npm/$package_name/versions" |
+      jq -r --arg cutoff "$CUTOFF_DATE" '.[] | select(.created_at >= $cutoff) | .name' |
+      sort -V)
+  else
+    versions=$(GH_HOST="$SOURCE_HOST" GH_TOKEN=$GH_SOURCE_PAT gh api --paginate "/orgs/$SOURCE_ORG/packages/npm/$package_name/versions" |
+      jq -r '.[].name' |
+      sort -V)
+  fi
+
+  for version in $versions; do
     echo "$version"
 
     # get url of tarball
-    url=$(curl -H "Authorization: token $GH_SOURCE_PAT" -Ls https://npm.pkg.github.com/@$SOURCE_ORG/$package_name | jq --arg version $version -r '.versions[$version].dist.tarball')
+    url=$(jq --arg version $version -r '.versions[$version].dist.tarball' "${temp_dir}/${package_name}.json")
 
     # check for error
     if [ "$url" == "null" ]; then
-        echo "ERROR: version $version not found for package $package_name"
-        echo "NOTE: Make sure you have the proper scopes for gh; ie run this: gh auth refresh -h github.com -s read:packages"
-        exit 1
+      echo "ERROR: version $version not found for package $package_name"
+      echo "NOTE: Make sure you have the proper scopes for gh; ie run this: gh auth refresh -h github.com -s read:packages"
+      continue
     fi
 
-    # download 
+    # download
     curl -sS -H "Authorization: token $GH_SOURCE_PAT" -L -o $package_name-$version.tgz $url
-  
+
     # untar
     mkdir -p ./$package_name-$version
     # if you run into permissions issue, add a `sudo` here
     tar xzf $package_name-$version.tgz -C $package_name-$version
     cd $package_name-$version/package
     perl -pi -e "s/$SOURCE_ORG/$TARGET_ORG/ig" package.json
-    npm publish --ignore-scripts --userconfig $temp_dir/.npmrc || echo "skipped package due to failure: $package_name-$version.tgz" >> ./failed-packages.txt
+    npm publish --ignore-scripts --userconfig $temp_dir/.npmrc || echo "skipped package due to failure: $package_name-$version.tgz" >>./failed-packages.txt
     cd ./../../
 
   done