CHANGES.md in twilio-ruby-5.7.1 vs CHANGES.md in twilio-ruby-5.7.2

@@ -1,7 +1,16 @@
 twilio-ruby changelog
 =====================
 
+[2018-03-22] Version 5.7.2
+---------------------------
+**Preview**
+- Add `BuildDuration` and `ErrorCode` to Understand ModelBuild
+
+**Studio**
+- Add new /Context endpoint for step and engagement resources.
+
+
 [2018-03-09] Version 5.7.1
 ---------------------------
 **Api**
 - Add `caller_id` param to Outbound Calls API
 - Release `trim` recording Outbound Calls API functionality in helper libraries