If the unit was upgraded on the back of the chassis cj provided a sticker that basic stated series 2 and the date and maybe a new serial number ( can't remember that clearly).
Not sure on new units, however I am sure you could ask cj at what batch of serial numbers series 2 started if it is not on the back panel.
Not sure on new units, however I am sure you could ask cj at what batch of serial numbers series 2 started if it is not on the back panel.