SSL Renewal - timing and overlap with old certificate

[JustAsk]

I've received an SSL certificate renewal message. If I buy a 2 year renewal will the new certificate:

a) Be able to be authenticated & installed immediately i.e. will not need to wait until the old certificate has run-out;

b) Will I be given additional days credit on the new certificate equivalent to the unused days on my old certificate?

[rd]

If your current SSL certificate expires on September 5, 2018 and you purchase/renew for 2 years you can expect that you new renewal date will be September 5, 2020 Basically you just get 24 months added to your current time @JustAsk. I hope that helps?