Would I then be able to change it back to quarterly after I install everything I need?
That could potentially corrupt your entire system.
The problem is that binary packages have specific dependencies and you cannot change those yourself (unless you build the package yourself using the ports collection). Therefor all packages in the repository are carefully checked so that they share the same dependencies. Think about libraries and such.
So if this package uses specific libraries and you already have those installed on your system then you can safely assume that those libraries (and every other package which depends on them) will be upgraded.
If you'd then switch back to
quarterly you'd face 2 problems: you wouldn't get any more (security) updates because you already have a much newer version of the provided software. And worse: the moment you install something new which depends on a certain library then that library would get downgraded again, resulting in the removal of every package that depended on the newer version.
So I really wouldn't do this.
There is a change that this can work, but it heavily depends on the package you're trying to install and its dependencies. You could check FreshPorts for info on that.
(edit)
My Jail also uses the quarterly binary repository and I think you overlooked something:
Code:
root@psi:/ # pkg search elasticsearch | head -4
elasticsearch-plugin-head-2015.12.16 ElasticSearch Head Plugin
elasticsearch5-5.6.8_5 Full-text search engine for Java
elasticsearch5-search-guard-5.6.8 Elasticsearch Search Guard plugin
elasticsearch6-6.3.2 Full-text search engine for Java
root@psi:/ # grep url /etc/pkg/FreeBSD.conf
url: "pkg+http://pkg.FreeBSD.org/${ABI}/quarterly",
root@psi:/ # file /usr/local/etc/pkg/
/usr/local/etc/pkg/: cannot open `/usr/local/etc/pkg/' (No such file or directory)
Notice
elasticsearch5 &
elasticsearch6?
