Followup:

Hey everyone. I haven't gotten a response back from the support team but I did try troubleshooting the problem myself with various methods to some success. I disconnected my computer from the router and directly plugged it into the cable modem box to try and see if it was the router causing me problems. I only played for an hour or two on FFXIV but noticed that the R0's had stopped.

Since then, I reset the router back to factory defaults and have been testing FFXIV with multiple pc's logged on again to see if I could recreate the lag spikes/R0's. So far it hasn't had another R0 hiccup, though there have been some lag spikes while playing (nothing out of what I'd expect though as far as normal server lag goes).

So if any of you guys are having similar problems to what I described in the original post, try directly plugging your PC to the cable modem box itself to see if it could possibly be the router causing hiccups. If you notice the R0'ing stop, you might have to reset the router to factory settings (via a little button on the back side) or you may have to purchase a new router altogether.

If I get more R0 spikes later my next step will be to replace my router with a brand new one. Good luck!