Hi,

I believe the text you are seeing regarding the link will be set by the language of the server according to BOL here:

https://msdn.microsoft.com/en-us/library/ms156493.aspx

Specifically this line:

Errors, warnings, and informational messages that are returned by the server.

The language of the report with regard to the =en-US part will depend on the language setting of Internet Explorer. so if you change that it should change the parameter to fr-FR.

Here's how to change it:

http://stackoverflow.com/questions/25439775/ssrs-subscription-change-the-date-format-executiontime-on-the-subject-line