Standby Letter of Credit or SBLC is a pledge document issued by the bank to represent its customers. This document is the bank's commitment to pay to the supplier if the buyer / customer of the bank failed to make the payment as the last resort. SBLC facilities have a lifespan of 1 year 1 day.
The same goes for Mid Term Notes (MTN) and Long Term Notes (LTM) which has lifespan of 5 years and 10 years respectively.