Different Pick up times and changing the contract.

[MonkeyPrincess]

I have a parent originally write on their contract that they will pick up their child at 5:30 (closing time), but most of the time picks up earlier, like before 5. Every now and again they pickup just before 5:30 if they have a meeting, but i always have notice and i don't charge late fee because according to the contract, technically they are not picking up their kid late. I am currently re-doing my contracts for 2014. I would like to change their pick up time on the contract to 5pm. Can i change it and hand them their new contract with the new time or suck it up and continue with their original pick up time?- i shouldn't have to, right? Should i just change my closing hours? They are my last pick up, all others pick up before 5. I could get dinner and everything done a half hour earlier!