Background: I have my own authoritative certificate that I generated myself for signing certificates for services my friends and I use, including web server, ircd, etc. It's convenient because I don't have to spend money getting my certificate signed and among my those who use it, the guarantee of security is fairly complete.
Caveat: Being somewhat noobier then than I was now, I set my CA to expire after a year. This was about 10 months ago. The private key is 4096 bit RSA and the certificate is self signed with SHA512, so it should stay secure for pretty much as long as I'm around to care about it, as long as I don't lose the private key.
Question: I know I can generate a new certificate from the private key with a longer expiration date (say 100 years from now for the purposes of this discussion). Would the replacement be as simple a process as substituting the newly generated, extended certificate to all of the clients? Would they accept the subcertificates as trusted, provided they updated their stored copies of the CA to reflect the new expiration date? Would I be able to skip regenerating all of the intermediate certificates as long as the CA's keypair and fingerprint remained the same?