Update:  All of our Gen7 SmartVPSs now have the option of running PHP 7.4 on any site on your server. Some benchmarks claim that PHP 7.4 is 20% faster than PHP 7.3 and over 60% faster than PHP 5.6.  

Instructions are here: https://support.brownrice.com/content/2/283/en/how-do-i-upgrade-my-php-and-mysql-versions.html