Tasks Take a Long Time to Accept Completion/Cancellation

If I mark more than one or two tasks at a time as completed or cancelled, starting with the second or third one it takes what seems like at least a full minute for them to update to the new status. (I haven't timed it.) After that wait, they all update at once.

This appears to only happen on the current day. If I wait until the next day to update them by going back to the day before, they all change status there as soon as I tap.