It's been happening for at least the past few weeks. As previously noted it's ONLY happening in Frontlines. Up until yesterday I was getting DC'd once almost every other game; nothing worse than getting booted to have a queue + lose battle high progress. When it happens there is noticeable instance lag and the music will start cutting out.
Last night was probably the first night that I didn't get 90k'd while playing for several hours during peak times, although there was still some visible instance lag.
If I had to speculate I'd say this was likely the cause of the Moogle + Garo events ending and the mass influx of people PVP'ing are probably stressing the instances.
For the record, I'm also hard wired.
