We have decided to support an additional version of PHP: 7.2. In addition to 5.6 on RHEL/CentOS 7, we have 7.1 on the secondary web layer and now 7.2 on Fedora 28 beta.
Keep in mind that 5.6 only has a few months of support left. 7.1 isn't much better off. This crazy release schedule will kill them. If Unity can finally do a LTS release, why can't PHP? Anyway, you can find the details here and I'll go flag this as a rant.
Edit: (Subject updated) To clarify, 7.2 is not beta, nor is our deployment. It's just that Fedora 28 hasn't been released yet, so there may be some issues left to iron out.