how to make v2.6 ---> v2.5 so i can play in this server?

I've been playing InfiniteAion since last year. I've got high ping there so i searched and found this server and i wanted to play here because it's in Philippines where i live. The problem is IA is already version 2.6. Is there a way to to make this v2.5 since this server is still in version 2.5 or when will this server go version 2.6?

Please help and thanks a lot!