When I saw her sat on the steps in the trailer it wasn't Mary Poppins that came to mind,, but Eliza Doolittle. And as Eliza was taken from her life by Professor Higgins to be 'improved' and introduced to a whole new life that left her floating, unable to slip back into her old life but not quite belonging to the new one.. I thought that was going to be some link to the companions.
But, as we know who she is now, that doesn't fit.