Link: "mealpal.com/th6".
When you are selecting your plan, it will say "$50 Coles Voucher When You Sign Up Today!". Otherwise it might not work.
T&C copied from the website:
Your Coles eGift card will be sent (via email). Valid for new customers only. You will receive a Coles e-gift card within approximately 45 days of signing up. MealPal is a monthly subscription plan and will auto renew. You may change your plan or cancel your membership at any time. Limited to one $50 Coles e-gift card per new MealPal member. This offer cannot be combined with any other promotion. These terms are subject to change - See full terms of service. Coles is a registered trademark of Coles Supermarkets Australia Pty Ltd
So must join the plan not just sign up create new account, right?