AD9914/15 Bit 15:8 of CFR4 reads 0x21 after reset

On an AD9915, bit 15:8 of CFR4 reads 0x21 after reset. But the Rev A DS states: "Requires register default value settings (0x31)" on page 36.


Which one is correct? Or should the bits read 0x21, but require 0x31 on writes?