What does Double-cycle billing mean?

Double cycle billing is used by some credit card issuers, and it is a balance calculation method that allows these issuers to apply interest to two cycles of credit card balances, instead of the most recent cycle’s balances. This practice effectively eliminates any grace period for individuals who paid off their balance the month before.

This billing type was not accepted by customers, moreover federal regulators decided to ban the method, and it will be revoked at the beginning of July in 2010. This method is also known as two-cycle billing.