From my own experience of this problem...
ATC at this (UK) airport are not telling aircrew what minima to use - The Airport Authority (who are in the UK get their licence by following what it says in CAP 168) are following THEIR rules by declaring and NOTAMing that precision approaches (ILS) are not permitted because the required ground equipment is not all serviceable for that approach (ILS when Low Visibility Procedures in force). It's a weird one I agree! And as usual (snow clearing/slot times/eobt's etc) it's us in ATC that get caught in the middle.
Not being a professional pilot I have to ask - under JAR-Ops do you have a published minima for a (normally) CAT 1 ILS that then becomes (effectively) an uncategorised one - are the approach plates still valid?
Keep on discussing
DD