Sorry friend, this is the case. There must only be one slot.
Interesting note re: RAM choices ... if you select the i5-5200U CPU on the Lenovo US website then you are allocated 4GB of RAM and have no option to select 8GB. The mid-range CPU (i5-5300U) allows you to select either 4GB or 8GB. Finally, if you select the i7-5600U then you are allocated 8GB and can't select 4GB.
Not that I've had the chance to try it out but the concept seems great, especially for people aged 50+ IMO.
http://store.sony.com/digital-paper-system-zid27-DPTS1/cat-2... [Sony]