Actually all the Relay cels that you mentioned and also called 
Post Production cels of those series are coming with newly 
made sketches for the Relays.
To put it into my own words of 
what I was told is that those series are CG anime and there are 
pencil sketches but those sketches are made for CG and of no use 
to make the Relay cels. So Animators newly draw pencil 
sketches for the Relays. 

I own a Relay cel myself and I ask 
before I bought it many questions and what I was told is that no 
original sketches that were used in the CG anime are coming 
with the Relay cels or also called Post Production 
cels.

If you interested in more info you can contact RAXA 
for more information since they are the licenced dealer to 
sell overseas the Relay cels.

Here is their 
website:
http://hobby-shop-raxa.cside.to/Relays/

I 
hope this info clears a few things up about Relay/Post 
Production cels.

Trish