I just got a message today saying my subscription was expired. I was about to renew it, but I remembered that I'm planning to send my laptop in for repairs. If I do, they'll most likely reformat everything. I don't want to risk renewing now, and then having to buy the subscription all over again simply because the program was deleted from my computer.
When you renew your subscription it will be valid for as long as the period that you purchased. Most renewals go for a year but sometimes folks purchase a 2 or a 3 year renewal. You can download McAfee for as many times as you need to over the life of the subscription as long as it is valid.