Today mid-day, I told Siri "Remind me at 7 PM to do such-and-such." She confirmed creation of the reminder. At 7:30 I sat down at my mac and pulled up ToDo Cloud. I went to Inbox and saw the now overdue reminder.
I checked my phone - no alerts showing on the lock screen.
I opened ToDo Cloud on my iPhone and went to Inbox. It showed one old task, then refreshed and showed me the two that ought to have been there -- one overdue and one not quite due.
It looks like the reason I got no notification was because the task had not synced, therefore there was nothing for the phone to alert upon. Whatever the reason, though, this severely limits the usefulness of this tool. If it doesn't sync until I look at it, what's the point of having alerts?
Is there something I need to set to tell it to sync promptly?
(That it's dependent upon a sync at all is kinda strange from the end user perspective. I used my iPhone to create the task, why does the phone need to sync to receive the task it just sent? I understand the technical reason, but it's still cumbersome from the end user standpoint when the sync is not prompt.)
FWIW I've seen missing notifications as well although they do not seem related to slow Siri sync. I opened a ticket on this problem in October 2014, saw some recent activity on it and thought it might have been fixed in the current version but it happened again to me recently. #75544 Task alerts do not pop up reliably on iPhone (iOS 8).