Why Apple Reminder app on iPhone 7 / iOS 13.3.1 does not have hourly repeat option? I've been looking for ways to set up an hourly reminder. I've find a number of online article saying that starting with iOS 13, the native reminders app has an "hourly" option in the repeat menu.

Yet my native / Apple Reminders app doesn't have an Hourly repeat option. I have an iPhone 7 with iOS 13.3.1 installed. I have tried to delete / reinstall the app, still no "hourly" option.

What am I missing? Is there something I can do to change that?
Had the same problem with an iPhone 11 Pro, so it's definitely not the age of the phone.  Could reliably follow the instructions from this answer on an older Xs, but Hourly would just refuse to show up on the 11 Pro.
Then I noticed that the summary page on the 11 Pro (tap &lt; Lists in upper-left from any list) had a link Upgrade right around the heading My Lists (sorry, didn't think of taking a snapshot), and tapping it asked for a confirmation (the upgrade is irreversible &amp; breaks compatibility with other devices sharing the same lists using older software--see this Apple Support page), and then voila!, Hourly magically appears in the list of base periods on the Repeat screen.