Reference for Pesachim 240:10

אוקים לילות במקום ימים ויהא נאכל לשני לילות ויום אחד כתב רחמנא הזה

If so, what is taught by 'in [that] night? ' You might think that it can be eaten like [other] sacrifices, [viz. ,] by day: therefore it is stated, 'in [that] night': it is eaten by night, but it may not be eaten by day. Now how does R'Akiba employ 'that [night]'?