Yes, that is from the Pre War shipment. I do not believe any of the 1946 guns were Flat Tops. When I see a Flat Top LETTERED to the 1946 deal, I'll believe it.
I thought the OP's gun might be a Round Top because the "Made in USA" is not visible. That took a lot of buffing. It was on both orders, but it was smaller and shallower on some of the 46 guns.
Yes, it's quite unfortunate that it was apparently buffed away, but it's something I can live with all things considered.