Yep, this is all in regards to a Sept 2017 fight. Apparently these little negotiations took place when Golovkin was scheduled to fight Brook and Canelo set to fight Smith.
After Khan, there were no negotiations at all. Canelo dropped the belt and said he was going to 154. Cool, whatever, Golovkin gets his belt and they each make a fight. At some point after, Golden Boy contacts k2 about a potential fight in late 2017. A few days ago Oscar said he would only offer Golovkin a flat fee, no percentage, no PPV upside. Now Canelo/Oscar are saying something a bit different than that, so who knows what was offered. Tom Loeffler confirmed there was a little bit of negotiations but didn't go into a specifics, just said his phone is on and if they want a fight now they can have it. Reading between the lines seems obvious K2 want a fight now or at least after Golovkins mandatory (Danny Jacobs) and Oscar wants it for one year from now.
I think there is some good news here though and that is the two sides have been talking, which is far better than no talks at all, which is what we had thought. So thats good. I think what will happen is they will enter serious negotiations after each have a fight (hopefully GGG vs Jacobs and Canelo vs Saunders). Either way, I don't think anything is going to happen till next year anyway so who cares about talking now when they aren't going to fight next anyway.