Just so you know they also have to wait for cPanel to release PHP 5.6 to the WHM so really you should ask cPanel to update to 5.6 and then once you know that gets updated then ask here
Resurrecting this thread. According to PHP, active support for 5.5 ended 10 Jul 2015. Security updates will stop 10 Jul 2016 (in 3 months). What's the plan of upgrade? 5.6 which would buy us two years until 12/31/2018 or 7 which is stable as of last December