So in summary : I think we should continue to use CentOS-7/Final as the
main distro that everyone runs, and use the 7.YYMM to indicate the isos
set, with metadata inside the installed machine still reporting whatever
rhel point release it originated or maps to. Everything that has
happened in the past, stays intact - except the ISOS release is
announced as '7 1406 - rebuilt from RHEL 7.0 sources'.

Fairly lost now, doesn't take much I'll grant but there we go.
 
In all the organisations I've ever worked at we've kept our own mirrors of each X.Y directory/step and then at some places kept snapshots of those per month by postfixing them in spacewalk with YYYYMM when cloning channels via cron job.

Just referring to CentOS 5, 6 or 7 without the .Y is so vague as to be meaningless in any technical or patching discussion.

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Regards,
   Phil