No offense, but that’s not really much of an answer beyond “it’s that way just because”. “Interval” suggests a regular pattern, while the Weekly function is, in every single other app I’ve ever used, intended for custom distributions by specific weekday. Is there some sort of boundary problem with the code that it can’t handle an iteration of 1? Or did the developers simply overlook that fundamental use case? Those things happen, no big deal — but there are actual solutions.