Heathrowinnit
No special regs for the An-225, and that is 50 tonnes heavier. Never had a problem when it flies in UK airspace, but then again the laws of physics are different here....hence the rest of the world has one set of wake vortex spacings and our tiny little bit of air has a completely different set?????
The air around Heathrow is different again, allowing an extra layer of wake vortex sub-groups to aid landing rate.