I also am searching for root info on ZTE Max XL N9560. So far I have found recovery mode, FTM mode and what appears to be DFU mode. The DFU is the most interesting so far but only because it seems to be the Qualcomm emmc serial port access. The trouble with this phone is that its running android N which looks to have "shared" folder links to which you seem to have write access but the underlying folders do not, so you cannot write. If anyone has any info on the serial commands to interface with the qualcomm emmc, please point me in the right direction, I am willing to use my device for testing.