Found this in the Operations Manual, so I take it that it anwsers my question:
EHM operates a relaxed aircraft substitution policy. While we would like every pilot to fly
every flight in a plane wearing our livery, we understand that not all of our planes work
perfectly in all sim platforms. Therefore if an official EHM plane does not work well in your
simulator, you may use a different aircraft for the flight AS LONG AS it is fundamentally the
same type and size of plane eg instead of a Piper Arrow you could use another single engine
prop like the Tomahawk; instead of the Embraer 170 you could use another regional jet like
the Canadair CRJ-700. Please note any such substitution in the Pirep comments box.
:-)