When I first went to LHR - in the Arrow - we were asked by ATC if we could maintain 180 knots to the outer marker. Negative.
We did offer 140kts to the threshold if we could "land long", as we needed to slow down before extending the undercarriage (in the flare and subsequent "float").
I was told that light twins are allowed into LHR but a single could not approach the 27's and still be able to glide clear in the event of an engine failure - dunno about the 09's.
I also thought, however, that a licensed aerodrome was PROHIBITED from political selection of which aircraft it WOULD accept, and that all operators were to be given equal access (assuming air law, runway slots, handling etc).