Update laravel 5.0 to 5.1 on a server with php below 7

I am running a laravel 5.0 app and I am planning to upgrade to 5.1 to gradually get to 5.4, I'm using an Arvixe server with SSH, CPanel and WHM access I know 5.1 needs PHP 5.6.30 to run and right now my application is running with PHP 7.0 but in order to do it I had to change in Cpanel the php selector to PHP 7 because by default PHP 5.4 was in place and now when I try to update my app is telling me that php version is below requirements I even try to install laravel 5.1 from 0 and I am getting the same error, is that and indication that my server has only PHP 5.4 and is so how I was able to change the PHP selector to 7?

what I can do to update my app?

via Chebli Mohamed