Well, I see you posted the full number elsewhere here on the Forum. Here is what you provided:
This one most likely shipped in April or May of 1947. I show about 50 of them that shipped in those months, ranging from S880xxx to S905xxx. There are many gaps in my data at that point, but clearly a lot of M&Ps went out the door in that serial range during those two months.
Looking forward eagerly to seeing some pics of your revolver.