If you don’t have an Apple computer but have an iOS device, you can also do something similar with the “Shortcuts.app” + “Calendar.app”. I have a daily shortcut that runs at X time. Shortcut checks a calendar for events, if today contains one or more events. It will parse the text from these events (comma separated fully qualified phone numbers or iMessage accounts), and send the message contained in the body of the…
Last time i checked you need to swipe to confirm every time your automation attempts to send a message? kinda kills the automation part. I was shocked that there was almost nothing to be automated with messages on IOS as third party apps can't even read or send them. The Tasker app for android is great for this kind of thing.
I have an old iPhone that runs this automation. Haven’t touched it in many months. Still runs without a hitch.