My girlfriend has an older iPhone that cannot be updated to iOS 13. I've avoided updating the reminders on my own iPhone so that we can continue to sync. I'd like to update to Catalina on my mac, but I don't want to do it if it will prevent her from syncing with me.
Can I continue to use the old reminders database on my mac and iPhone until she gets a new iPhone in the coming months? Or will Reminders.app refuse to work without updating the database?