Always. Running a re-opt in campaign, even if you know you have at least implied consent, will allow you to get express consent, meaning less worrying about time limits. In addition, it will ensure that you have proof of consent from all your customers, and your bases will be covered. Erring on the side of caution in your dealings with CASL will be rewarding, even if it means a little more work. This is not to say there is anything wrong with implied consent. You need to be sure that you have proof of consent and can say that you have some kind of consent. For additional questions, you can visit our CASL page or contact us at email@example.com.