Wrong time in Mailing Report
Glad to have been able to help - reposting my comment as a response and kindly requesting that you mark it as accepted given your findings.


  When you've got things running on different servers, there is a chance that dates and times may be mismatched - e.g. your mail server might be configured with a time zone that is different from the server on which your civi instance is installed and hence the time is incorrectly translated. Determining whether this is the case would be the first step. 


Glad I could be of help!