not a full upgrade to Office 2013

I bought 2010 Home and Student about 1 week before Office. The product includes 3 licenses for a user.
I have Office 2010 on my installieret three PCs. Everything is wonderful. Says on the box that you can upgrade Office 2010 to Office-2013.

This week started Upgrade and found that you can not all 3 User Upgrade as long as you do not want a subscription.
In other words, you want the full maturity can be only one PC on Office 2013 Upgrade. Will you can change every 3 PCs is only for 1 year subscription.

Under these circumstances, I would not buy Office 2010. Amazon Customer refers to the Microsoft Customer Service. The only writes one that you have to call the expensive hotline and otherwise yes find everything information on the Internet.
Neither on the packaging or in the information provided at purchase is what a subscription to upgrade! Very kundenunfreundlich if not targeted deception!