How long does Branding free last
 

If I buy the branding free version and in lets say....2 years time VB5 is released* do I have to pay for branding free again if I want to upgrade to VB5 or as I have paid for branding free once* I won't have to pay for it again. I am aware that I will have to pay for the upgrade to VB5 but this question is just regarding the branding free cost.

On another note* if I buy VB4 today* can I start using the CMS and forums today or do I have to pay now and wait for the gold version