breaking changes

Author: mongoKart

source/upgrade/v2.txt

@@ -135,6 +135,11 @@ Version 2.19.0 Breaking Changes
      clientSettings.LinqProvider = LinqProvider.V2;
      var client = new MongoClient(clientSettings);
 
+  If your application uses the LINQ3 provider, you can't use ``-1`` to represent the
+  :manual:`positional operator </reference/operator/update/positional/#mongodb-update-up.->`
+  when updating an array. To learn how to use the positional operator, see
+  :ref:`<csharp-update-one-arrays>` and :ref:`<csharp-update-many-arrays>`.
+
 Version 2.14.0 Breaking Changes
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