Why would they indicate intent and continue to accept conversions after 80% if they don't want 100% of NWE?
The only thing afforded to them at 90% is compulsory acquisition. If they didn't intend to just get 100%, they would have removed the offer early and done as you said, decouple the SP and pick the rest up at a much lower price.
The offer will continue until they get to 90% and then they will exercise their right to compulsory acquire.
