One thing I think we need to consider is that this ride is going to have to be compact; due to this I think the possibility of it being a launch coaster is significantly increased. Making it launched will mean they've got more room for actual elements and they haven't got a lift hill taking up unnecessary room. Another point is what manufacture could do something like this? To me the list in endless, examples include: Vekoma (who Drayton have used before), Intamin (who Drayton has used before), Zamperla (who Drayton has used for flat rides in recent times) and Premier (who no UK park has ever worked with). As @DistortAMG says apocalypse needs some serious refurbishment works so I wonder if they've done a deal with Intamin to refurbish apocalypse and build a new coaster? That certainly seems a possibility. I think the most likely though is Vekoma, we've seen them do launch coasters at a really reasonable price recently and I think getting the most amount of good quality coaster for the money will be important.