Ping Problems since the 10% GP+ Event

Since the 10% GP+ Event started for 2 weeks ago I've got 250 ping/status on Alpha Server and Bravo Server etc. I used to have 150. But on UK Server I still got the same ping as before: 200.

I think that something must happened to the servers that day. And all the other people that got the same internet provider as me got the same problem.

So what can I do? I can't change internet provider.