This campaign has started since 2 days ago (June 18th), and will run all the way till July 11th. That's about a month for your to order your items from the website.
The discount is offered to all ordered with payment method set to Paypal. Currently, the company offers two payment methods: Paypal and credit card. This offer is valid for the earlier only.
The discount is offered to both EMS and SAL types of shipping method. You can check for the discounted rate on this page.
More information can be seen on the official site's newspage about this campaign.
Image is from Hobby Search.