TEC > Template overrides for the month view to include all events in the "Month view events per day" setting.

calendar-events.php

<?php
/**
 * View: Month View - Calendar Events
 *
 * This is an override for the following template:
 * wp-content/plugins/the-events-calendar/src/views/v2/month/calendar-body/day/calendar-events.php
 *
 * Override this template in your own theme by creating a file at:
 * wp-content/themes/[your-theme]/tribe/events/v2/month/calendar-body/day/calendar-events.php
 *
 * See more documentation about our views templating system.
 *
 * @link    http://evnt.is/1aiy
 *
 * @version 4.9.8
 *
 * @var array $day_events                An array of the day event post objects. Each event is a `WP_Post` instance with additional
 *                                       properties as set from the `tribe_get_event` function.
 * @var array $number_of_multiday_events The number of multi-day events.
 *
 * @see     tribe_get_event() For the format of each event object.
 */

// Bail if there are no events for day.
if ( empty ( $day_events ) ) {
	return;
}

// New part to calculate how many multi-day events are there.
$month_limit = tribe_context()->get( 'month_posts_per_page', 12 );
$remains     = $month_limit - $number_of_multiday_events;
// End new part
?>

<?php foreach ( $day_events as $event ) : ?>
	<?php
	// New part for counting
	if ( $remains <= 0 ) {
		break;
	}
	// End new part
	?>
	<?php $this->setup_postdata( $event ); ?>

	<?php
	$this->template( 'month/calendar-body/day/calendar-events/calendar-event', [ 'event' => $event ] );
	// New line, decrease remaining
	$remains --;
	?>
<?php endforeach; ?>

cell.php

<?php
/**
 * View: Month View - Day cell
 *
 * This is an override for the following template:
 * wp-content/plugins/the-events-calendar/src/views/v2/month/calendar-body/day/cell.php
 *
 * Copy this template to your own theme by creating a file at:
 * wp-content/themes/[your-theme]/tribe/events/v2/month/calendar-body/day/cell.php
 *
 * See more documentation about our views templating system.
 *
 * @link    http://evnt.is/1aiy
 *
 * @version 5.3.0
 *
 * @var string  $today_date         Today's date in the `Y-m-d` format.
 * @var string  $day_date           The current day date, in the `Y-m-d` format.
 * @var array   $day                The current day data.{
 * @type string $date               The day date, in the `Y-m-d` format.
 * @type bool   $is_start_of_week   Whether the current day is the first day of the week or not.
 * @type string $year_number        The day year number, e.g. `2019`.
 * @type string $month_number       The day year number, e.g. `6` for June.
 * @type string $day_number         The day number in the month with leading 0, e.g. `11` for June 11th.
 * @type string $day_url            The day url, e.g. `http://yoursite.com/events/2019-06-11/`.
 * @type int    $found_events       The total number of events in the day including the ones not fetched due to the per
 *                                  page limit, including the multi-day ones.
 * @type int    $more_events        The number of events not showing in the day.
 * @type array  $events             The non multi-day events on this day. The format of each event is the one returned by
 *                                  the `tribe_get_event` function. Does not include the below events.
 * @type array  $featured_events    The featured events on this day. The format of each event is the one returned
 *                                  by the `tribe_get_event` function.
 * @type array  $multiday_events    The stack of multi-day events on this day. The stack is a mix of event post
 *                                  objects, the format is the one returned from the `tribe_get_event` function, and
 *                                  spacers. Spacers are falsy values indicating an empty space in the multi-day stack for
 *                                  the day
 *                                  }
 */

$day_id = 'tribe-events-calendar-day-' . $day_date;

$month_limit = tribe_context()->get( 'month_posts_per_page', 12 );

$more               = $day['found_events'] - $month_limit;
$day['more_events'] = max( $more, 0 );
?>

<div
	id="<?php echo esc_attr( $day_id ); ?>"
	class="tribe-events-calendar-month__day-cell tribe-events-calendar-month__day-cell--desktop tribe-common-a11y-hidden"
>
	<?php $this->template( 'month/calendar-body/day/cell-title', [ 'day' => $day, ] ); ?>

	<div class="tribe-events-calendar-month__events">
		<?php $this->template( 'month/calendar-body/day/multiday-events', [
			'day_date'         => $day['date'],
			'multiday_events'  => $day['multiday_events'],
			'is_start_of_week' => $day['is_start_of_week'],
		] ); ?>

		<?php
		// Modified part to add multi-day events
		$this->template(
			'month/calendar-body/day/calendar-events', [
				'day_events'                => $day['events'],
				'number_of_multiday_events' => count( $day['multiday_events'] ),
			]
		);
		?>
	</div>

	<?php
	// Modified part to recalculate "more events"
	$this->template( 'month/calendar-body/day/more-events', [
		'more_events' => $day['more_events'],
		'more_url'    => $day['day_url'],
	] );
	?>

</div>

multiday-events.php

<?php
/**
 * View: Month View - Multiday Events
 *
 * This is an override for the following template:
 * wp-content/plugins/the-events-calendar/src/views/v2/month/calendar-body/day/multiday-events.php
 *
 * Override this template in your own theme by creating a file at:
 * wp-content/themes/[your-theme]/tribe/events/v2/month/calendar-body/day/multiday-events.php
 *
 * See more documentation about our views templating system.
 *
 * @link http://evnt.is/1aiy
 *
 * @version 4.9.4
 *
 * @var string $day_date         The `Y-m-d` date of the day currently being displayed.
 * @var array  $multiday_events  An array representing the day "stack" of multi-day events. The stack is composed of
 *                               events post objects (instances of the the `WP_Post` class with additional properties)
 *                               and spacer indicators.
 *                               The stack is pre-calculated for the day, events and spacers are in the correct order.
 * @var bool   $is_start_of_week Whether the current day is the first day in the week or not.
 *
 * @see tribe_get_event() For the format of the event object and its properties.
 */

if ( 0 === count( $multiday_events ) ) {
	return;
}

$remains = tribe_context()->get( 'month_posts_per_page', 12 );
?>

<?php foreach ( $multiday_events as $event ) : ?>
	<?php
	// New part for counting
	if ( $remains <= 0 ) {
		break;
	}
	// End new part

	// If we receive a falsy value, then we need to add a spacer in the "stack".
	if ( false === $event ) {
		$this->template( 'month/calendar-body/day/multiday-events/multiday-event-spacer' );
		continue;
	}

	$this->setup_postdata( $event );

	$this->template( 'month/calendar-body/day/multiday-events/multiday-event', [
		'day_date'         => $day_date,
		'event'            => $event,
		'is_start_of_week' => $is_start_of_week,
	] );
	
	// New line, decrease remaining
	$remains--;
	?>

<?php endforeach; ?>