Here is an update regarding the S9 March 2019 firmware.

as far as the firmware goes, all of my gears have been running smoothly without an issue, temps are fine, hashrate reported by the pool is good, nothing really to complain about.

but as far as the downgrading of the firmware, i have tried every possible solution at my disposal with no luck, not that i  "need" to flash another firmware, but i don't like that fact that i have to be stuck with this firmware. it is really annoying.

I have contacted Bitmain, they were pretty straight forward and said there is nothing they would about it, in other orders they said "you have to live with it".