When do I redeem savings bonds to pay for college?

[davidsgibson]

If I redeem savings bonds to pay for college, do I have to actually redeem the bonds before I pay tuition, or do I just have to redeem them in the same year that tuition is paid, and is there any paper trail necessary to show that the bond proceeds were actually used to pay tuition?

[SweetieJean]

This sems to say the same year:

If the amount of the redemption proceeds from all eligible bonds redeemed during the year exceeds the amount of the qualified educational expenses paid during such year, the amount of excludable interest will be reduced pro rata. 

https://www.treasurydirect.gov/forms/savpdp0051.pdf