Hi coz,
I have got the similar issue, after I upgraded the firmware from 4.4.2 to 5.3.1, all OK, after that, I upgraded the firmware form 5.3.1 to 5.4.4, after reboot, it was showing 4.4.2.
then I upgraded the firmware to 5.3.1 again, and then to 5.4.4 then 5.7.0, no issue.