I think most pilots understand that different units will interpret things differently, and different controllers at the same unit will also have different approaches. I don't expect the new rules will change that. But for commercial flights outside CAS it's reasonable for them to expect some consistency and predictability. As part of the safety case approach now required by CAA it seems to me that at the very least the airline's Ops Manager or Chief Pilot should head along to the relevant Area Centre and LARS unit(s) with a copy of their Ops Manual under his arm, so both sides know what's going on. Again, this is irrespective of whether a new ATSOCAS system is introduced.
NS