Each auction has "period to be secured" information, which indicates the minimum period the Bank Guarantee has to be valid to be taken into account while calculation the credit limit for the particular auction. This information can be found in eCAT Auction Tool in the "Auction" tab / Auctioning parameters.
If the Bank Guarantee expires before or on the mentioned date, unfortunately our system will not include it in the credit limit calculation for that particular auction, as it would not cover the whole required "period to be secured". Therefore, we always recommend to check this information in our Auction Tool, so that you could control you collaterals.