Web API 2 with JSON.net - globally apply DateTime format

Question

I seem to be missing something somewhere. Hopefully someone can spot it and I can get on with my life safe in the knowledge that I need to look harder in future:

I have been trying to configure a WebApi 2 project, which uses JSON.net serialiser.

EDIT: my endpoints are odata 2 - I am pursuing if this makes a difference.

I want the DateTime format to universally be something other than ISO. I understand that the ISO format is the ideal one for the purpose, however at the moment my client library is not handling this well, and for a quick-and-dirty I want to exchange Dates and DateTimes using the same format as required for display/edit. This will buy me the time to write the customised modifications of the client library's Date/DateTime controls. My scenario usefully does not call for actual localisation so in the short term I am safe to use this approach.

So, having followed various threads and guides including: http://james.newtonking.com/archive/2009/02/20/good-date-times-with-json-net

Custom DateTime serialization with Json.Net

Set default global json serializer settings

I still do not seem to be able to get anything back other than the ISO date format. I have toggled the 'Formatting Indented' back and forth and I can see that is affecting my result fine.

Here is the config I am currently applying in my WebApiConfig.cs Register method. Can anyone help me with making the right configuration so that ALL Dates and Times are returned in either Javascript format, or using a custom JSONConverter for UK date format (dd/mm/yyyy HH:mi:ss):

    JsonMediaTypeFormatter jsonFormatter = GlobalConfiguration.Configuration.Formatters.JsonFormatter;
    JsonSerializerSettings jSettings = new Newtonsoft.Json.JsonSerializerSettings()
    {
        DateFormatHandling = Newtonsoft.Json.DateFormatHandling.MicrosoftDateFormat,
        DateTimeZoneHandling = Newtonsoft.Json.DateTimeZoneHandling.Utc,
        NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore,
        Formatting = Newtonsoft.Json.Formatting.Indented, // For dev only set json to prettyprint
        Culture = new CultureInfo("en-GB"),
    };
    //jSettings.Converters.Add(new UkDateTimeConvertor());
    //jSettings.DateFormatString = "dd'-'MM'-'yyyy' 'HH':'mm':'ss";
    jSettings.Converters.Add(new JavaScriptDateTimeConverter());
    jsonFormatter.SerializerSettings = jSettings;