If you want to offer early bird discounts, you should follow the steps below:
1. Go to Marketing>Promotions
2. Click on your Promotion or set up your Single code promotion or Multiple coupon code promotion (Groupon, LivingSocial).
3. In the Early bird section, tick the Enable checkbox. Select when you want to apply early bird discounts. For example, you can offer a discount only to customers who make their bookings at least one month before the booked date.