When a PDF is created on the server the server time is used to request a website or SmartForm.

The parameter could be used to overwrite the timezone so the DateTime-Field the user entered will be the same on the generated PDF.

Example:

Server Timezone: CET, User Timezone: CET + 1. SmartForms will render the value as they were entered by the user. The server-side PDF generation will display the users timezone -1 hour.