Subscription start date (or effective date) in the UTC time zone, in YYYYMMDD format.

Mandatory parameter used for creating a recurring payment.

This parameter does not always match with the date of the first installment that depends only on the vads_sub_desc parameter.

Example: for 1 February 2015, use 20150201.

Input and output field, returned in the response (IPN and Return URL).

Format n8
Error code 69
Category Subscription details.