py-borgbackup - why isn't the package there?

The archivers/py-borgbackup port is listed on Freshports as having a package, py36-borgbackup. But when I try to install it, pkg can't find it:
root@www# pkg search borg
py27-borg.localrole-3.0.2_1    PAS plugin which can manage local roles via an adapter lookup
this machine is using the quarterly repository
root@www# pkg -vv | grep url
    url             : "pkg+",
so it could be that. However, I looked in all the repositories (both latest and quarterly) at and the package isn't anywhere to be found. Looking at the port history (thank you Freshports) it looks like the NO_PACKAGE issue this port was "born" with was fixed last year. So why is the package missing?
This is probably the reason:
    IGNORE= you have python ${PYTHON_DEFAULT} set as the default, and this needs ${PYTHON_VER}
PYTHON_DEFAULT is currently 2.7. The port's USES however states it needs Python 3.4 or higher. So it triggers the IGNORE rule.
The machine in question has everything installed from packages (quarterly) repository. How badly am I going to mess up the system if I install borgbackup (and what it needs) from ports?
It's probably going to be ok. It should be possible to have both Python 2.7.x and Python 3.x installed, so I don't expect any conflicts. But keep an eye on what exactly is going to be installed.

However, if you change the DEFAULT_PYTHON setting, you're bound to get conflicts as this would mean everything that requires Python is going to be updated and changed.