C602 Chipset and PCIe Gen3

I've been working recently on a Supermicro X9QR7-TF+/X9QRi-F+ server. I took the user's manual and saw two things: the chipset is Intel C602, and the expansion slots are PCIe 3.0.

According to Intel's website C602 chipset supports PCIe 2.0.

Furthermore, the user's manual states:

The C602 chipset provides extensive IO support, including the following functions and capabilities: (1) PCI-Express Rev. 2.0 support (2) PCI-Express Gen. 3 uplink supported by some SKUs

What does "uplink supported by some SKUs" mean? So does it support Gen3 or not?

If SuperMicro says their implementation supports it, and Intel says it's available on some SKUs (that is, some specific versions of the chipset), then I don't see any reason to believe why that server wouldn't support PCIe 3.0

What does "uplink supported by some SKUs" mean?

I would assume that it means on some variants of the chipset the "uplink" (that is the connection from the chipset to the CPU) can be PCIe gen 3.

So does it support Gen3 or not?

AIUI all the downstream PCIe ports on the chipset are PCIe gen 2. The upstream link from the chipset to the CPU may or may not be gen 3.

However the PCIe slots on your motherboard are not connected to the chipset! They are connected directly to the CPUs. The CPUs each have 40 PCIe gen 3 lanes available (of which your motherboard only uses a small fraction).