I’d use Reminders to set up an individual reminder for each daily instance (one for 7:30 a.m., one for 8 a.m., one for 8:30 a.m., etc.) and set each of those to repeat on weekdays. That’s a lot of fiddling at first, but you wouldn’t have to mess with them after that. I do something similar for a thing I do three times a day.
It’s so weird that you have posted this, because my back was playing up this morning (ahead of a whole day on Zoom, of course) and I thought to myself that the stand alert on Apple Watch does not work (I ignore it) and I idly wondered whether I could set up some kind of Apple Shortcut to do alerts, and if the forum would know how to do it. THEN I wondered if there was an app that already exists and nudges people to move at a frequency of their choosing. And I figured the forum would know if that existed.
And I log on this evening (with a sore back…) and you’ve saved me a task!
Good health and safety hygenie of not sitting all day is essential. I have now come to rely on my Apple Watch which automatically puts up a reminder for me to stand up and move about when it senses no movement. This feature only appears to function between 9AM and 5PM.
The other feature of the Watch is “Stand Hours”. It records when I have stood up and moved about for at least one minute in each hour of the day. The taunt for when I have not done that is it marks the hour as “Idle”.
Both features have helped me not to get oedema again. Stupidly earlier this year I sat for hours and hours binge-watching TV programmes and in consequence brought on oedema. Required a visit to my GP and a short course of diaretic tablets along with putting my feet up to get rid of it. Oedema can be painful.