WRA Gas Cylinder Period Question

A couple of days ago a guy over on the CMP forum was asking about whether a narrow or wide base cylinder would be correct for an early 2.4 million Winchester (I can't remember the exact serial, but think it was something like 2,410,XXX).

Looking at my Duff red book, it states that the switchover was sometime in the fall of 1943, so I'm thinking that is the 2.3 million range.

But didn't WRA sometimes use earlier cylinders on later rifles? I pretty sure they did with other parts.

Even so, wouldn't this be considered a transitional period and therefore either could be correct?

Anyone ever see an original 2.5 million or WIN-13 with a narrow base cylinder? Or by then was it really a wide base cylinder game?

Anyway, thank you all for your input. I feel bad that I couldn't come up with a definitive answer for this person and I wouldn't say yeah or nay without really knowing it. I know there is always new information coming to light with respect to Garands and so without having the most up-to-date information, I just don't know.

I have a WIN-13 April '45 with the narrow base gas cylinder with the ledge or step under the dovetail. This is a DCM rifle. I think by the WIN-13 period any parts combination is possible.
I have no idea to the transitional WRA serial number period for the narrow and wide base. Maybe some WRA specialists will contribute.