Moving to another droplet, SSL Certificates already installed on the droplet for a domain, need to do something on the certificates?

I’m upgrading Droplet to another region that has Volume, is there any thing I need to do with SSL Certificates already installed on the droplet for a domain?

I’ve created an image from my droplet, created another droplet with the image, and at original one had SSL certificates installed for the domains it was serving with nginx, than I changed DNS to point to the new droplet ip, started the applications, everithing seems to be working fine, is there any thing I need to do with the SSL Certificates on the old droplet? They were generated from that machine.

Or can I destroy that droplet? Are the SSL certificates going to be fine on the new droplet? Need to extract it? I tested the website and it seems to be good, working with SSL certificate already on the image.