Longer Free Trial Period for Affiliate leads

Hi,
We would like to give new members a longer free trial period for leads provided by some affiliates.
Is there an easy way to do this?

Further explanation:
We usually give new users 30 days free trial, then they will have to subscribe. However, we have a special agreement with a number of affiliates (not all of them) to give 60 days free trial before they are required to subscribe. What is the best way to setup this?

Thanks in advance
Carmelo

Perhaps create a product/signup page for these affiliate leads?

David

This would be a good option.
But I don't know how to redirect the default affiliate links to the new signup page.
Currently the link is https://mysite.com/aff/go?r=xx
How can I redirect the above to the new signup page?

Thanks in advance
Carmelo