I didn't ask further with the local sale about the details. We just send the link of the product to the sale and they said it will be end of life. So I guess that includes both SDK and JRC.
On the other hand, I am also a customer of SAP, so I will not be able to answer when the SDK will support WebLogic 12c.
So far I haven't see any official reply on this kind of question, so I will just assume it will never support WebLogic 12c.