Yeah, this is where we're at. We have a ton of old servers running hundreds of sites, some of them up to 10 years old. It's just not feasible for us to upgrade those servers unless there is a massive security issue. So we have a lot of servers running 5.3 and 5.4.
We currently run on Debian stable and don't upgrade any packages beyond what Debian is supporting. In all likelihood, we won't be using PHP 7 until the next major Debian release, which I believe is scheduled for April 2017.
Regardless, we still have to support clients that are running older instances of PHP on their GoDaddy shared hosting. If it's not EOL, we can't justify not allowing them to use it so we're stuck with 5.5+ for the time being.