Emergent consensus has nothing to do with this. Forget anything to do with BU, that's been long forgotten by the power players. Any reference to EC in their block signature is there for legacy reasons and doesn't remotely mean they're interested in BU any more. BU supporters will insist this isn't the end for them and that it's still compatible with segwit2x, but then so is XT, classic and any other defunct attempt at a takeover from the past that never activates and stays on the current chain waiting to take it over at some unforeseen parallel universe future. Forget EC.