No.
I use Flip for long time. When a new chip comes to me from factory and I connect Flip to its bootloader then BLJB is set. It is not fault, it is indicated in bootloader`s datasheet as a feature: as long as internal flash not programmed once it runs bootloader after power-up automaticaly even without bootloader hardware conditions. Nevertheless after chip has been programmed, it keeps BLJB at state which was before programming. It is my work to unmark it and write hardware/software bits with correspond button. Indeed, it is possible to configure Flip to unmark that bit itself after programming with checkmark "Set Specia; Bytes" but it is disabled by default. So I have indicated it as possible reason.

Regards,
Oleg