Calendar Notifications Plus does not appear in the listed app stores

[kekukui]

I need a reminder once per hour for 12 hours before the scheduled event. This would be used for miscellaneous event-related tasks that dont need to be itemized on the calendar. When I decide that all of these tasks are complete, I would then want to hit a button on the reminder notification that silences any remaining reminder or alarm for that event. The purpose of this is when you have tasks which must be done at any time before the alarm (as opposed to a literal appointment, which is inflexible.)

It seemed like this app might meet my needs, but I cant find it in the app stores.