What does the Technical Support active/expired means ?

My initial thoughts are that Technical support being active would relate to it being available ... and expired to something where technical support is no longer available. An old operating system like Tiger, for example.

If the matter is other than this, perhaps you could explain where you saw the term.

It means the warranty is still in effect - or not. If you are beyond the warranty, technical support is still available - for a price. If you call them for an issue, they will check the records using your serial number and will be able to determine if the support is covered or not.