Adding dates to conditions?

Is there a way to add dates to conditions?

For example my client wants to charge extra $15 per person per night for 3 – 6 people.
I’ve added that condition in separately for 3, 4, 5 and 6 people without any problem.
However from October 2013 she wants to increase her charges to $20 per person per night and I can’t see how to add that in as well as have the existing conditions in for 2012.

Does the Premium edition allow this?

No.

Thanks for the reply.

I’ve told my client to simply change the ones I’ve set up when she feels she needs to.