mg5077 Jumptoheaven On the Classic Flip FASTBOOT is nuked. Doesn't exist in the ABOOT. And the Exalt is a device I don't know much about, but considering Verizon's track record, (and the US Unlocked Samsung S7 and up being bootloader locked and signed at VZ's request)
I'm very likely to say it's got no FASTBOOT mode either, and if it does have it,
"fastboot oem unlock" is 98% of the time nuked on VZW phones...
However, holding END and Volume Down doesn't do anything but holding both, letting go of END, and pressing END again triggers a force factory reset. This is especially good for when you mess something up BAD and you can't get back out of it.