我觉得这是一个option on 3 month shibor 3 month forward.
根据现在的利率3个月后的3 month shibor should be 4.17%, so if 3 month later, the spot 3 month shibor is higher than 4.17%, bank will not exercise this option, as borrowing cost will be higher than to continue to borrow from lenders. If the spot rate 3 month later is lower than 4.17%, bank will exercise this option, to get lower rate from market for 3 month funding.