The firmware worked in the datacentre. It was tested on the hosting facility last night, then released today as it was deemed stable.

Just back from 7 miles with my dog and found my miners down.  Must have been cable work nearby.  

So, here's what I think.  If an ASIC module has one or more dies showing high cores being disabled, shut down the system, let sit a minute before unplugging cables from the module.  Remove the module's heatsink, remove the board from the unit.  Then with some gentle support under 1 VRM at a time, exert pressure down on the flat metal top.  Continue with each VRM supporting under that module as you do so.  Reassemble the unit.  Run enablecores.bin and if you see improvement it's not that the VRMs are providing improved power but that the VRMs are losing more heat from their top rather than there bottom.  When they lose heat from the bottom the heat travels by way of the PCB to the nearby ASIC module and the nearest die will come up with errors.  That one reason the lower the fans to the deck method works so effectively - it passes air between the VRMs and ASIC module.

You all are welcome.  I know this is helping my competition but then I've never been an overachiever.