@droftarts - Ian, thanks for the clarification and additional info. I always learn something from this forum. Knowing that the endstops are ignored on all but H0 helps me understand more clearly how it works.
The more important thing I learned is that there can only be one end stop per motor and the design we are using does indeed have two NC endstop switches wired in series. We have recently been contemplating separating these to two inputs because in normal use, this motor is at rest with one of them triggered. In this situation, we can only know which end of travel we are at rest on by keeping track of it in sw - a risky proposition that a second input would eliminate. Now we know there will be additional macro work to do if we follow that path (re-define the endstop before making any moves). That'll be something for us to really look hard at.