Welcome to the community, @Sasha_Moser! :grinning_face_with_big_eyes: Your logic looks pretty sound. Here’s one way to structure a formula that could be used to trigger an automation on those intervals:
Status = "Desired Value",
DATETIME_DIFF(NOW(), CREATED_TIME(), "days"),
That will output a 1 at any of those three intervals after the record’s creation date, but only when a given status is matched. At all other times during the status match, the output will be zero. If the status isn’t matched, it will be blank.
If you want the automation to behave differently at each of those intervals—perhaps by using conditional branches in the automation to send different emails—you could move the
DATETIME_DIFF() calculation to its own formula field so that the automation could have access to that value when triggered, and refer to that field in the above formula.