Need some Bearcat help

[Fox Mike]

I have noticed that some of my later (93) serial numbered Cats have the last three inscribed on the face of the cylinder and some do not. I called Ruger and the answer I got was "it depends on how many are in that run" which DOESN'T answer the question as WHEN did they start doing it. I posted the question on the rugerforum.com but the only answer so far was a 'supposition'. I was wondering that if you have a Bearcat could you check the cylinder and, if it HAS a number let me know by PM ( That way everyone will not see it). I will then start a list and try to determine the earliest that can be found.