How do I migrate the "Created" and "Modified" date fields? I created a migration script to test this out.

This is the code I used.

id: article_csv_import
class: null
field_plugin_method: null
cck_plugin_method: null
migration_tags: null
migration_group: Import articles
label: 'Import articles'
source:
  plugin: csv
  path: 'modules/custom/sigtarp_migrate/data/articles.csv'
  header_row_count: 1
  ids:
    - id
process:
  nid: id
  title: title
  body/format:
    plugin: default_value
    default_value: full_html
  body/value: body
  changed:
    plugin: callback
    source: update
    callable: strtotime
    created: date
  created:
    plugin: callback
    source: update
    callable: strtotime
    created: DateCreated
  status: Status
  type:
    plugin: default_value
    default_value: article
destination:
  plugin: 'entity:node'
migration_dependencies:
  required: {  }


When I run the migration script, this is what happen when both the Changed and Created fields are entered. 


  





  


This is the content of the CSV file used for the migration.


  


Why is the date off? How can I fix it?
Turns out that for created &amp; changed dates, they are stored differently than field_date's, you must convert these to Unix universal time.

  changed:
    plugin: format_date
    source: update
    from_format: 'm/d/Y'
    to_format: 'U'
    from_timezone: 'UTC'
    to_timezone: 'UTC'
  created:
    plugin: format_date
    source: DateCreated
    from_format: 'm/d/Y'
    to_format: 'U'
    from_timezone: 'UTC'
    to_timezone: 'UTC'