Merge pull request #1492 from segmentio/brennan/amplitude

Correct Amplitude/Alias description.

Author: brennan

src/connections/destinations/catalog/amplitude/index.md

@@ -448,7 +448,10 @@ Segment Alias call allows you to associate a Segment user's `previousId`
 with the user's `userId`, or what Amplitude refers to, respectively, as a
 `user_id` and a `global_user_id`.
 
-By default, Segment does **NOT** send Alias events to Amplitude. To forward Alias events from Segment, go to your Amplitude destination settings in the Segment web app, and set the **Enable Alias** setting to "on". Once enabled, Segment forwards both client-based and server-based Alias calls. Segment processes _all_ Alias calls before sending them to Amplitude, so you won't see a `usermap` request to Amplitude if you check your browser's Network activity after making a Segment Alias call.
+By default, Segment does **NOT** send Alias events to Amplitude. To forward Alias events from Segment, go to your Amplitude destination settings in the
+Segment web app, and set the **Enable Alias** setting to "on". Once enabled, Segment forwards Alias events from Segment's servers only. This means
+that Alias events reach Amplitude only when you're sending events from the client and have set your Amplitude instance's connection mode to "Cloud Mode",
+or are sending Alias events from a Segment server-side library (such as Node).
 
 > note ""
 > To use Alias, you must have the Amplitude Portfolio add-on enabled.