diff --git a/.github/workflows/test-action.yml b/.github/workflows/test-action.yml
index 9dc0a68..a6e6bdc 100644
--- a/.github/workflows/test-action.yml
+++ b/.github/workflows/test-action.yml
@@ -16,7 +16,7 @@ jobs:
   test-custom-version:
     runs-on: ubuntu-latest
     env:
-      TEST_VERSION: '1.19.0'
+      TEST_VERSION: '1.18.0'
       VERSION_OFFSET: 27  # internal version = minor + offset (v1.19 → v0.46)
     steps:
       - uses: actions/checkout@v4
diff --git a/index.js b/index.js
index e29ec8a..c1e33c0 100644
--- a/index.js
+++ b/index.js
@@ -3,12 +3,6 @@ const exec = require('@actions/exec');
 const path = require('path');
 const fs = require('fs');
 
-// Using latest as default
-const DEFAULT_FUNC_VERSION = 'latest';
-const DEFAULT_BINARY_SOURCE = 'https://github.com/knative/func/releases/download';
-const DEFAULT_LATEST_BINARY_SOURCE = 'https://github.com/knative/func/releases/latest/download';
-
-// Returns the binary name for the current OS/arch from GitHub releases
 function getOsBinName() {
     const osBinName = core.getInput('binary');
     if (osBinName !== "") {
@@ -47,116 +41,90 @@ function resolveFullPathBin() {
     return path.resolve(destination, bin);
 }
 
-// Normalizes version to release tag format: knative-vX.Y.Z
-// Ex.: '1.16' or 'v1.16' will return 'knative-v1.16.0'
 function smartVersionUpdate(version) {
-    const versionRegex = /^(?<knprefix>knative-)?(?<prefix>v?)(?<major>\d+)\.(?<minor>\d+)(\.(?<patch>\d+))?$/;
-    const match = version.match(versionRegex);
-    if (!match) {
-        throw new Error(`Invalid version format (${version}). Expected format: "1.16[.X]" or "v1.16[.X]"`);
+    const match = version.match(/^(?:knative-)?v?(\d+)\.(\d+)(?:\.(\d+))?$/);
+    if (!match) throw new Error(`Invalid version format (${version}). Expected format: "1.16[.X]" or "v1.16[.X]"`);
+    return `knative-v${match[1]}.${match[2]}.${match[3] ?? 0}`;
+}
+
+function resolveVersion() {
+    if (core.getInput('binarySource')) return null;
+    const version = core.getInput('version') || 'latest';
+    if (version.toLowerCase().trim() === 'latest') return null;
+    return smartVersionUpdate(version);
+}
+
+function resolveDownloadUrl(version, binName) {
+    const binarySource = core.getInput('binarySource');
+    if (binarySource) {
+        core.info(`Using custom binary source: ${binarySource}`);
+        return binarySource;
+    }
+
+    if (!version) {
+        core.info('Using latest version...');
+        return `https://github.com/knative/func/releases/latest/download/${binName}`;
     }
-    const knprefix = 'knative-';
-    const prefix = 'v';
-    const patch = match.groups.patch ?? 0;
-    return `${knprefix}${prefix}${match.groups.major}.${match.groups.minor}.${patch}`;
+    core.info(`Using specific version ${version}`);
+    return `https://github.com/knative/func/releases/download/${version}/${binName}`;
 }
 
-// Downloads binary from release URL and makes it executable
 async function downloadFuncBinary(url, binPath) {
     core.info(`Downloading from: ${url}`);
-
     await exec.exec('curl', ['-L', '--fail', '-o', binPath, url]);
 
     if (!fs.existsSync(binPath)) {
         throw new Error("Download failed, couldn't find the binary on disk");
     }
-
     if (process.env.RUNNER_OS !== 'Windows') {
         await exec.exec('chmod', ['+x', binPath]);
     }
 }
 
-// Adds binary directory to PATH for current and subsequent steps
 function addBinToPath(binPath) {
     const dir = path.dirname(binPath);
     fs.appendFileSync(process.env.GITHUB_PATH, `\n${dir}`);
-
     if (!process.env.PATH.split(path.delimiter).includes(dir)) {
-        process.env.PATH = process.env.PATH + path.delimiter + dir;
+        process.env.PATH += path.delimiter + dir;
         core.info(`${dir} added to PATH`);
     }
 }
 
-// Resolve download url based on given input
-// binName: name of func binary when it is to be constructed for full URL
-// (when not using binarySource)
-function resolveDownloadUrl(binName) {
-    const binarySource = core.getInput('binarySource');
-    if (binarySource !== "") {
-        core.info(`Using custom binary source: ${binarySource}`);
-        return binarySource;
-    }
-
-    const versionInput = core.getInput('version') || DEFAULT_FUNC_VERSION;
-    if (versionInput.toLowerCase().trim() === DEFAULT_FUNC_VERSION) {
-        core.info("Using latest version...");
-        return buildUrlString(DEFAULT_FUNC_VERSION);
-    }
-    const version = smartVersionUpdate(versionInput);
-    core.info(`Using specific version ${version}`);
-    return buildUrlString(version);
-
-    function buildUrlString(version) {
-        return version === DEFAULT_FUNC_VERSION
-            ? `${DEFAULT_LATEST_BINARY_SOURCE}/${binName}`
-            : `${DEFAULT_BINARY_SOURCE}/${version}/${binName}`;
+async function warnStaleVersion(version) {
+    try {
+        const res = await fetch('https://github.com/knative/func/releases/latest', {
+            method: 'HEAD',
+            redirect: 'manual',
+        });
+        const loc = res.headers.get('location');
+        if (!loc) return;
+
+        const latest = loc.split('/').pop();
+        const toNum = (v) => { const m = v.match(/(\d+)\.(\d+)/); return m && m[1] * 100 + +m[2]; };
+        const diff = toNum(latest) - toNum(version);
+
+        if (diff >= 3) {
+            core.warning(`You are using func ${version}, which is ${diff} minor versions behind the latest (${latest}). Upgrading is recommended.`);
+        }
+    } catch {
+        core.debug('Skipping stale version check');
     }
 }
 
 async function run() {
-    let osBinName;
-    try {
-        osBinName = getOsBinName();
-    } catch (error) {
-        core.setFailed(error.message);
-        return;
-    }
-
-    let url;
     try {
-        url = resolveDownloadUrl(osBinName);
-    } catch (error) {
-        core.setFailed(`Failed to resolve url: ${error.message}`);
-        return;
-    }
-
-    let fullPathBin;
-    try {
-        fullPathBin = resolveFullPathBin();
-    } catch (error) {
-        core.setFailed(error.message);
-        return;
-    }
+        const osBinName = getOsBinName();
+        const version = resolveVersion();
+        const url = resolveDownloadUrl(version, osBinName);
+        const fullPathBin = resolveFullPathBin();
 
-    try {
         await downloadFuncBinary(url, fullPathBin);
-    } catch (error) {
-        core.setFailed(`Download failed: ${error.message}`);
-        return;
-    }
-
-    try {
         addBinToPath(fullPathBin);
-    } catch (error) {
-        core.setFailed(error.message);
-        return;
-    }
 
-    try {
+        if (version) await warnStaleVersion(version);
         await exec.exec(fullPathBin, ['version']);
     } catch (error) {
         core.setFailed(error.message);
-        return;
     }
 }