If you want to continue support and update then you need to renew license.Licenses are valid for one year from the date of purchase. When your license expires you’ll be able to renew your key via your account page.
If you cancel your membership subscription, then you cannot download plugins from the list. You cannot access the Forum Support also. You can either choose to remain with us and renew your subscription and grow with us enjoying our regular updates. ...
No, after customization also, you cannot resell the plugin. If you get a permanent license, you can sell it to your customer for business purposes. Normally we do not giving permanent license to anyone.