Released on: Tuesday, 23 June 2015 08:46
This version requires PHP 5.3.4 or later (e.g. 5.3.29 which is twenty five versions newer than PHP 5.3.4), 5.4, 5.5 or 5.6 or 7.0. Please note that PHP 5.3 is obsolete since August 2014 and we're going to stop supporting it without warning in future versions of our software. We'd like to remind you that most third party software which can be backed up by our software do not support PHP 7. As a result we can't guarantee the trouble-free operation of the restoration procedure if you are using PHP 7. Also keep in mind that PHP 7 is currently in pre-release stage and it's not a good idea using it in production environments anyway.
Note: there is no such thing as PHP 6. PHP versions jumped from 5.6 to 7.0. Why? Well, it's a long story. TL;DR: It doesn't have to make sense, just accept it.