Dual Bladers

So I've heard that you could only create DB's for a limited amount of time, and now you can't anymore. Is this true, and if so, what's the reason?

(Obviously this is about KMS)

It is. They might come back again, but at the moment you can no longer create them.

As for the reason. Many people say it was so KMS could earn more money.

I believe nexon Korean made Dual blades a limited time offer for the sole purpose of getting money, as can be seen with their ploy for CS based skill mastery books. previously they hadn't made much on new classes, so they opted to make a special offer to make it seem better for people to buy the class asap.