What is the link "Only offer support to new buyers" under description?

Today i am planning to update one of my item and found a link under the description “Only offer support to new buyers” am afraid to press the link.

could you please any one explain it?

If you don’t want to provide support to the customers who have bought your theme before the 1st of September, click it. BUT, I suggest you to not. This will only make your customers confused.

Besides, that option is going to be useless on the 1st of March. Just wait for 2 weeks.