Journey Builder can be used to send a weekly coupon campaign with a reminder three days later at the subscribers' optimized send time. Journey Builder allows users to create cross-channel customer journeys that deliver personalized messages at the right time and on the right channel. Journey Builder can use Einstein Send Time Optimization to determine the optimal time to send an email based on each subscriber's past engagement behavior. Reference: https://help.salesforce.com/s/articleView?id=sf.mc_jb_journey_builder.htm&type=5 https://help.salesforce.com/s/articleView?id=sf.mc_jb_einstein_send_time_optimization.htm&type=5