An example of how to pull an array of datetimes assigned to an event, resetting the $datetimes so that $datetime contains the next upcoming datetime for that event.

next_datetime_example.php

<?php
//Pull a list of upcoming datetimes from the event and reset the array to return the first (next upcoming)

EE_Registry::instance()->load_helper('Event_View');

$event = EEH_Event_View::get_event();

$datetimes = $event->datetimes_ordered($show_expired = FALSE, $show_deleted = FALSE);

$datetime = reset($datetimes);

//echo the day
$datetime->e_start_date('d');

//echo the month
$datetime->e_start_date('M');

//echo the year
$datetime->e_start_date('Y');