Arisaka T38 carbine butt plate?

Does anyone know when the type Arisaka type 38 carbine butt plates changed from steel to the cupped one or is that a manufacture's change.
thanks scott

I’ve never seen a Type 38 Carbine with a cupped butt plate.

Are you sure it’s a Type 38?

I may have been thrown by two carbine stocks I spotted for sale with cupped butt plates. I see now that they are Chinese made and so are replacements. Good thing i did not buy them.
Thanks Scott

I took just a few minutes to search Arisaka type 38 carbines photos and more than a few came up with cupped butt plates. Several claiming to be all original take homes.
scott

Looking in the excellent book "The Type 38 Arisaka" by Allan, the Nagoya series 4 (May 1936 to June 1941) changed to cupped butt plates later in the series. The 5th and 6th series had cupped butt plates also. (1941 and 1942)

(I can't remember all this stuff. That's why I buy the books on everything I have)

Go here. The 'Gallery' links work. Not seeing anything that would be described as a 'cup' though.
http://www.nambuworld.com/arisakas.htm

thanks, scott