My access to newsgroups is through Google and they don't do asap

Lay a straightedge against the existing wall and see if there is room
for the mud at the corner, if so leave the corner bead.
Because it is an oudside corner you can just hacksaw a kerf through
the corner bead 1/2 in from the cieling and remove it from that point
down and not disturb the cieling if you do end up removing it.