I tried Airtel too using my friend's phone but even using Airtel I wasn't able to access the site.
After reading your post I had to do a quick search and I found out that Airtel is being used in more than 15 countries, I have always thought it was just a local internet service provider I never knew it was International. That's probably the reason it is very fast when using it.
By the way, I'm glad you could access it using the mirror links - I started recommending it to others after I saw bcgame representative recommend it to someone else and it solved their problem of being unable to access the site too.