Why is E160 27.5 only in Small?

[billium]

This bike is top of my short list right now but I want a small in Mullet and Whyte say
"S and S sizes come with 27.5in wheels both ends for balanced handling"
All the other brands I am looking at that sell Mullets have them in any size - Specialized, Orbea, Canyon
Any idea why Whyte can't/won't sell me a Mullet in small?

 

[Ark]

the E-160 S is the 29er version of the E-160

The MX is mullet.

but oh yea not if you want Small, I guess it's because of the frames geometry