Potential routing issues with World of Warcraft

I play World of Warcraft on US servers for social reasons. Generally I have a ping of 100-120, it's manageable. Over the past few weeks, I have routinely experienced periods of continuous disconnects from the servers, as well as lag spikes. Sometimes I cannot log back into the game, and sometimes I can. This is not really happening in any other context - watching videos, playing other games online, downloading files are all fine.

I did a bit of digging and it seems that quite a few people have been experiencing this recently. I found this battle.net thread which suggested testing a VPN. While playing through a VPN, while my ping is slightly higher (130 or so), I no longer experience any erratic connectivity. A poster in that thread speculated that Blizzard did some kind of routing change in response to recent DDoS attempts:

A subsequent poster indicates their issue was resolved after talking to their ISP. I don't know much about this topic, but is it possible that there is something that can be done on Virgin Media's side to looking into whether there is a routing issue?

Thanks.