1. If the repayment dates of the two cards are staggered, withdraw the A card, and the funds withdrawn will be used to return the B card.

2. On the repayment date of Card B, withdraw cash from Card A for returning Card B..

3. As long as both Card A and Card B can withdraw cash, and the withdrawal amount can cover the repayment amount of the other card, then the two cards can repay each other.