Florence Knoll lounge collection  

I'm having a little trouble establishing whether a Knoll armchair is authentic and am hoping someone could help with a couple of questions:
1) The leather sides of the armchair is panelled rather than in one single piece like the latest Knoll ones. Is this something that existed on older versions? Am struggling to find vintage leather examples.
2) How recent did the Chinese fakes start to be manufactured? The chair clearly has some age to it, but difficult to tell the difference between a 20 and 40 year old chair sometimes...
Many thanks in advance. Will post pictures if I go ahead with the purchase!