I am playing from Malaysia for almost 5 years, and it has been quite stable previously with about 240-250ms latency. Recently after the SAB event went live, I have been experiencing severe lag spike up to 5000+ms latency randomly. The game is totally unplayable without using VPN. Even with VPN, the latency sometime spike over 400-500ms randomly.
I am pretty sure my internet is fine with other games, only with Guild Wars 2 it has been a nightmare.