Update errors-page-find-fix-verify-problems.mdx

EOL notice for APM Errors classic UI

src/content/docs/apm/apm-ui-pages/error-analytics/errors-page-find-fix-verify-problems.mdx

@@ -27,7 +27,7 @@ redirects:
   - /docs/apm/applications-menu/events/view-apm-error-analytics/
 ---
 
-With Errors in New Relic One, you can see the line of code that's causing a bad experience for your users, and get enough data to reproduce the issue so you can fix it. When you do, you’ll be able to confirm your fix is working in production.
+With the **Errors** UI in New Relic One, you can see the line of code that's causing a bad experience for your users, and get enough data to reproduce the issue so you can fix it. When you do, you’ll be able to confirm your fix is working in production.
 
 Use **Errors** in New Relic One to:
 
@@ -39,6 +39,10 @@ Use **Errors** in New Relic One to:
 
 ## View the APM Errors page [#error_procedures]
 
+<Callout variant="important">
+  As of October 1, 2021, the APM **Errors (classic)** UI will be discontinued in favor of the New Relic One APM **Errors** UI. For more details, see our [Explorers Hub post](https://discuss.newrelic.com/t/important-upcoming-changes-to-support-and-capabilities-across-browser-node-js-agent-query-builder-net-agent-apm-errors-distributed-tracing/153373).
+</Callout>
+
 To view the **Errors** page:
 
 * Go to **[one.newrelic.com](https://one.newrelic.com) > APM > (select an app)**, then click the **Error rate** table's title on your selected app's **Summary** page.