Buying Used Vehicle but Suspicious Number Plates

[user-xxx]

I want to buy used car but i see many of them with fake number plates that look like original but they dont have YEAR Number Mentioned on them for eg ABC 456 or LHR 359 so why the year is not mentioned ?

My own car has fake plates put number is real like ABC-20-3543 and it can be verified online and its on my name.

So what are these numbers without year ?
How to verify those ?

[hash4u]

Probably trying to copy new punjab plate format
Btw if buying car check smart card and file
Number will stay with owner anyway

[user-xxx]

I Asked the question from excise and they told me that car numbers before 2006 were without the year. so those are fine.