744Focal, speaking for my company, we would not often land flap 30 at LHR,. We would tell ATC if unable to maintain 160 to 4 early on. And anyway at normal landing weights Vref + 5 flap 25 is around 145-155 kts. Think i had 162 kts once but that was a collection of unusual circumstances. (tankering fuel) As max ZFW is 245T you have to have 40t fuel in tanks to be at max landing weights and the speeds you suggest. So even max ZFW plus a generous arrival fuel of 15t only puts you at 260t (but dont have the speeds on me but i think 158?)