Not an Adminer myself, but I thought Substitution Pay was paid only in those situations where someone was doing their boss's job at the same time at their own?
The pay is not just designed to recompense those covering a slightly more senior post than they might normally be expected to do, but also the additional time necessary to cover the extra post.
By the way, have the MACRs themselves brought this up officially? I've never met one who couldn't stand-up for himself!
I'll be amazed if we ever get the MRA4; I can't believe there's enough money in the pot.
STH