Customer.io seems closest! Nobody else does this, I have like 100's of transactional use cases: - Trial almost ending - New signup - CC expired - Reminders, co

Customer.io seems closest! Nobody else does this, I have like 100's of transactional use cases: - Trial almost ending - New signup - CC expired - Reminders, confirmations - Workouts affirmation, reminder etc. etc. A pain to write a proper rule system and keep overview in own application. The challenge is not the simple emails / notifications. But to combine it with more complicated rules, and and + time conditinos I have the events already in the system, would love to transfer them and have a stable UI / where I can add, create pause etc.