Since you have been subscribed to a season pass plans before, you can activate your 10% discount when you want to renew your plan or purchase a new season pass plan.
Follow these steps to get the 10% discount applied:
1) You should have already added any “season pass” plan(s) to your shopping cart.
2) Click this link to activate your discount.
3) Scroll to the bottom left, and check out the applied discount.
4) You can now proceed to the checkout page and complete your purchase.
Note that only season pass plans are eligible for the subscriber discount.