Brian,
Yes, I am aware that we are talking of two different aircraft named 'Aries' here.
I don't think PD328 was actually a Lancastrian. All information I have refers to it as a Lancaster, albeit a streamlined version for the purposes of it's long distance flights.
It may be that the Lancastrian design was based on PD328, but I don't know that.
Cheers
Southender