Have you tried this? https://bitcointalk.org/index.php?topic=1597639.msg18267781#msg18267781

EDIT: I can confirm that it resets a R4 batch-6 back to BMiner v1.0 file system date Tue Aug 9 21:00:51 CST 2016.
It also resets all pool info back to Factory so you will have to re-enter it.

Good bit is: Auto-tune is GONE! IT GIVES BACK FREQ and FAN SPEED CONTROL!

To do:
Power off miner
Press and hold in the IP REPORTER button.
While holding the button in, turn ON the miner power
Continue to hold in button for 5-7 sec and release
Wait a few min an you should be able to re-enter your pool info.
Enjoy!

Caveat: Since it runs BOTH boards at the same freq, if one is er, weak, you would have to downclock the good one until the weak one is happy....
Or apply the correct R4 update and get Auto-tune back...