Swaps factors, question, structure, 420, discount

Walex

There is a question on the schweser mock(exam1, q 117) that made me really confused about the value of a swap after some time period have passed. say 120 days have passed, we're looking for the value for the fixed and floating. It is a 2yr pay fixed
To value the fixed side, they're using the discount factors for days 60 , 240, 420, then 600...thats with the new term structure after 120 days....I have no clue as to why they use these. Shouldn't he use 600, 480, 360 and 180????