Sorry I'm not very familiar with C#, I'm in charge of SSRS related issues.
Do you mean want to export SSRS report as Pdf file as per schedule? If it's a single file, you can use file sharing to deliver it.
If you want to use C#, you can refer to this link: https://social.msdn.microsoft.com/Forums/en-US/fb61c11b-f873-4924-9ef4-dbb694fed580/how-to-export-the-ssrs-reportxls-or-xlsx-format-at-given-physical-location-through-c-code?forum=sqlreportingservices.
Best regards,
Aniya