This references lists the address code length as 6-bits. It is actually 7-bits. This only matters if you are trying read the PROD_ID register.
The next revision of this datasheet will replace the "6" (yellow highlight) with a "7." Until then, please be assured that this bit is active and that you can read the PROD_ID register, using DIN = 0x4A00 to request the contents of this register (which will flow out on DOUT, during the following 16-bit SPI sequence).