My name is Caleb and I'm a member of Constant Contact’s API Developer Support.
The V3 API does not have the ability to sort contacts / campaigns directly, however we are able to create a request which would provide a response that you can then use to parse and sort the data for the 'created_at' and 'updated_at' times you need.
To help gather more relevant data we are able to filter both contacts and campaigns based on the 'updated_at' value that the contact / campaigns currently have.
For contacts this can be achieved by setting your parameter as 'updated_after' and setting the value as the appropriate updated_at time (ISO-8601 Format) to get more relevant responses. There are further examples of how to do this as well as other criteria that you can use in the link provided below.
Get a Collection of Contacts:
An alternative method to filtering by the updated_at values for contacts would be to make a request to create a .csv file which would contain both values which you can then parse the response for the data.
For campaigns you will need to set the parameter as either 'before_date' or 'after_date' and set the value to the appropriate updated_at time (ISO-8601 Format) to gather more relevant responses. You may also use these parameters to get a range of campaigns last updated within a specific time-frame. I have provided the link which explains this process in further detail below.
Get a Collection of Emails:
Please have a look and let us know if you have any other questions!