Category
Retention playbooks are diagnostic before they are creative. They start by working out why customers actually lapse, because 'has not bought in 90 days' is a symptom and the three customers hiding behind it need three different emails.
Mine order data for the patterns that predict a second order, pick the right moment for each, and sell again without teaching full-price buyers to wait for discounts.
Map what each signup was actually promised, sequence five beats that keep that promise, and measure the flow against your list baseline instead of against zero.
Work out why customers actually lapse, segment by that reason rather than by days since order, and send a sequence per reason.