[SiriusHardware]

So, a non-fatal error. That would explain why no-one has tripped over it before now. Maybe someone realised that instruction was redundant and changed it in the source, from which the code was then generated. I assume the original code causes no harm, other than to waste a couple of instructions on an unnecessary act.

I believe you once told me (years ago) that the ninth display could be enabled with the addition of a simple wire, in which case the original instruction presumably would serve a purpose?