My Company is about to go to CC from CS6. Some questions re this

If we get 6 seats, can I install on more than that but only have 6 going at once? We have a number of users that only use it occasionally and its a pain to have them change computers to use it.

If we have more than 1 license of a CS6 suite (Web design, Production Premium etc), can we get multiple upgrade discounts?

Many thanks

Mike