add filter for cron interval time

vip-jetpack-sync-cron/vip-jetpack-sync-cron.php

@@ -1,10 +1,10 @@
-<?php 
+<?php
 
 /*
 Plugin Name: VIP Jetpack Sync Cron
 Description: This drop-in plugin ensures that Jetpack only syncs on the dedicated cron task.
 Version: 2.0
-Author: Rebecca Hum, Automattic 
+Author: Rebecca Hum, Automattic
 */
 
 use Automattic\Jetpack\Sync\Actions;
@@ -19,7 +19,7 @@ class VIP_Jetpack_Sync_Cron {
 
 	/**
 	 * Initiate an instance of this class if one doesn't exist already.
-	 * 
+	 *
 	 * @return VIP_Jetpack_Sync_Cron instance
 	 */
 	static public function init() {
@@ -42,7 +42,7 @@ static public function init() {
 
 	/**
 	 * Class constructor for hooking actions/filters.
-	 * 
+	 *
 	 * @return void
 	 */
 	public function __construct() {
@@ -54,21 +54,33 @@ public function __construct() {
 
 	/**
 	 * Filter to add custom interval to schedule.
-	 * 
+	 *
 	 * @param array  $schedules
 	 */
 	public function jp_sync_cron_schedule_interval( $schedules ) {
+
+		/**
+		 * Allows for overruling the Jetpack Sync Cron Interval time.
+		 *
+		 * If cron jobs are bottle necking, lowering this value will increase
+		 * jobs and may help elevate the queue. It may also cause too many
+		 * threads, so keep an eye on performance after changing.
+		 *
+		 * @since 2.0
+		 */
+		$interval = apply_filters( 'vip_jetpack_sync_cron_interval', 60 );
+
 		$schedules[ self::SYNC_INTERVAL_NAME ] = [
-		    'interval' => 60,
+		    'interval' => $interval,
 		    'display'  => esc_html__( 'Every minute' ),
 		];
-		
+
 		return $schedules;
 	}
 
 	/**
 	 * Filter to return custom cron interval name.
-	 * 
+	 *
 	 * @param string  $incremental_sync_cron_schedule
 	 */
 	public function filter_jetpack_sync_interval() {