Happy Birthday to you!
Thank you for activating your double points.
You'll now get double points on all purchases from your local Waterstones or on Waterstones.com until the date stated on your email. That can be as many purchases as you want until the date stated on your birthday email. Once your purchase has been made the points will automatically be added to your account within 48 hours.
Have a great week filling those gaps on your bookshelf (and celebrating your birthday).