Xdrip+ has a feature where you may receive a notification when the time of a future carb entry arrives. This may serve as a nice reminder to start eating when announcing a meal in the future while giving a pre-bolus. This would typically be within a time frame of 10 - 45 minutes.
It could be useful to only get such notifications for future carbs that are a limited amount of time ahead (user settable "pre-bolus" time), in case one does not want to be notified of carbs related to future entries representing fat/protein. Such entries are typically one or more hours into the future.