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where {id_sending} is the unique identifier of the sending to consider. The result is the date UTC date specified with the format described in the section 'Type and cast definition' of this page: http://help.mailup.com/pages/viewpage.action?pageId=22806545."Paging and filtering".
Update message
This method allows you to modify an existing message (content and settings).
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It is possible to specify an eventual date/time for a deferred sending, using the 'datetime' querystring parameter (UTC value), with the format described in the section 'Type and cast definition' of this page: http://help.mailup.com/pages/viewpage.action?pageId=22806545."Paging and filtering"
Example: POST /Console/List/2/Email/30/Send?datetime='2014-10-20 05:00:00Z'
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