rpm: what does the release number in `gpg-pubkey-<verstion>-<release>` stands for?

Question

GnuPG public keys that are imported into the RPM keyring with:

rpm --import PUBKEY_FILE

can be queried with

rpm -q gpg-pubkey-<key-id>

For example the CentOS4 key:

pub  1024D/443E1821 2005-02-25 CentOS-4 key <centos-4key@centos.org>
     Key fingerprint = 31EA 27E5 6F79 0C18 AD79  18DF A53D 0BAB 443E 1821
sub  2048g/06870DBC 2005-02-25 [expires: 2015-02-23]

can be queried with

rpm -q gpg-pubkey-443e1821

and the result is:

 gpg-pubkey-443e1821-421f218f

The RPM's version number 443e1821 corresponds to the key id 0x443e1821 but what the release number 421f218f stands for?

Answer 1

I cross posted this question on LinuxExchange, and got the answer there.

In short the release number: 421f218f, is the Unix time of the key creation:

$ date -d "1970-1-1 + $((0x421f218f)) sec"
Fri Feb 25 13:01:03 IST 2005