CBSubs unclear how to setup Renewal

hello

I'm a bit unclear how to setup Renewal for my paid plan. Due to my poor english understanding, I don't understand exactly the allowed options.

Actually I choose: Renewal start at expiration date or at payment date - witchever happends last (allow free gap)

I don't see what is exactly the term "free gap" and "overlap" and I need to be sure to what will happen...

My plan is a paid plan for a duration of 1 year. The user will be allowed to renew his plan 3 month before expiration. So by admitting user subscribe today, the plan will be active from 5.12.2011 until 5.12.2012. Now if user decide to renew his plan before the 5.12.2012 and he are in the correct "time slot" allowed of 3 month, my goal is to allow renew from 5.12.2012 until 5.12.2013.

So for what I understand the renewal option I choose is correct and the plan will be extended from the 5.12.2012 (if user renew before expiration) and his remaining period will be always keep OR from the payment date (if user renew after expiration).

It is correct ??

thank

So for what I understand the renewal option I choose is correct and the plan will be extended from the 5.12.2012 (if user renew before expiration) and his remaining period will be always keep OR from the payment date (if user renew after expiration).

It is correct ??

Yes, that is correct.

If they renew in advance it will extend their subscription by another year after their current year.

If they however expired and renewed 3 days afterwards it would continue from the point of payment and not from when they expired for example.