[Milsurplus] FW: SCR question

[Hubert Miller]

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-----Original Message-----
From: Hubert Miller 
Sent: Monday, May 18, 2020 5:45 PM
To: milsurplus at mailman.qth.net
Subject: SCR question 

So I surmise this nomenclature designation, like SCR-**-number-number-number, later was unified into this style representation: SCR-number-number-number-*  ( *= letter ) .
Is that right ? When did that change appear ? 
I hope this message is not too suspicious. 
-Hue Miller