Given that it's gone to a public consultation (as with Exodus and Project Amazon), my natural assumption would be that it's going to happen at some stage in the not too distant future, or at very least is currently intended to. Towers would be unlikely to do a full consultation if they didn't have some concrete intention of bringing this project to fruition, surely? Surely the "testing the waters" phase would mostly have been done privately? (I'm led to believe that parks do often liaise with the local council before publicly making planning applications or doing consultations to check that what they're planning is likely to get approved)
Based on Exodus and Amazon, my bet is that they've got a pretty finalised design and have already got 99% of the details sussed. Merlin trotted out identical lines in those consultations even though there were some pretty striking indications that they already knew exactly what they wanted to build, so while it is possible that Towers are still choosing, I also think it's very possible that they've already chosen and are simply keeping it secret until later. Like
@Dave said, I reckon the ambiguity is the park giving themselves wiggle room in case there are any slight modifications made.