I’m not 100% sure to be honest. It seemed to work fine for me this morning but then by lunch time the lag kicked in again. I still think its worth Blizzard investigating from their end.
Here is another response from ABB on the issue and what they are doing
Blizzard are bringing up a couple of 100G PNI’s with us in Sydney shortly, I’ve just finished our side of the configuration today and some physical cabling to get patched in hopefully early next week, and then Blizzard to do their side and we’ll have a heap more capacity directly into Blizzard now for the next round of gaming updates 
I am unsure if they’re going to send us additional routes, but it’s very likely we’ll see things like World of Warcraft oceanic realms/instances and other Blizz games route over these new links also.
I’d be keen on some feedback once they’re live.
I guess if this is the issue, then waiting another week or so really sucks 