[dos1]

Originally Posted by h1uke

I confirm that typing bist fastboot to a uboot prompt causes the
PW to enter the USB Recovery mode:

Spoiler:

uboot > bist fastboot


U-Boot 2009.08-lab126 (Sep 06 2012 - 16:08:16)

CPU:   Freescale i.MX50 family 1.1V at 800 MHz
mx50 pll1: 800MHz
mx50 pll2: 400MHz
mx50 pll3: 216MHz
ipg clock     : 66666666Hz
ipg per clock : 66666666Hz
uart clock    : 24000000Hz
cspi clock    : 54000000Hz
ahb clock     : 133333333Hz
axi_a clock   : 400000000Hz
axi_b clock   : 200000000Hz
weim_clock    : 100000000Hz
ddr clock     : 266666666Hz
esdhc1 clock  : 80000000Hz
esdhc2 clock  : 80000000Hz
esdhc3 clock  : 80000000Hz
esdhc4 clock  : 80000000Hz
MMC:  FSL_ESDHC: 0, FSL_ESDHC: 1
Board: Celeste WFO (256 MB)
Boot Reason: [POR]
Boot Device: MMC
Board Id: 00A15011241414IF
S/N: B024150224420FW8
I2C:   ready
DRAM:  256 MB
Using default environment

In:    serial
Out:   serial
Err:   serial
POST done in 1 ms
Battery voltage: 4058 mV

running cmd: fastboot
Entering fastboot mode...
Battery voltage: 4058 mV
USB speed: HIGH
Connected to USB host!
Charger disconnect
USB speed: HIGH
Connected to USB host!
USB configured.

it exits back to a bist> prompt when the USB cable gets disconnected.

That's great news, thank you! So there's a hope for poor spirits like mine who carelessly upgraded to 5.3.0 before its true evil nature was found out, thank you once again!