As you probably know, the first Coffee Lake-S desktop processors were revealed earlier this week and will start shipping on October 5. The latest version of Intel's desktop roadmap reveals we an expect a batch of new Intel Pentium Silver and Intel Celeron processors in the October-November timeframe. These BGA (soldered) models are based on Gemini Lake, there will dual-core and quad-core SoCs with a 10W TDP. The slide below indicates these parts are expected between October 23 and November 7, 2017.
Next we can see that Intel's other 300-series chipsets and the lower-end Coffee Lake-S processors will follow in Q1 2018. This will include dual-core, quad-core and six-core parts with a 35W and 65W TDP. The additional 300-series chipsets include the H370, H310 and B360. Intel had to change the naming of its "B350" to "B360" because AMD is already using the former.
Another minor update is that Intel will be launching its Optane 900P SSD at or near CitizenCon, an expo centered around Star Citizen. This event is scheduled on Friday, October 27th. Intel will reveal 280GB and 480GB Optane 900P SSDs.
Gamers Nexus also backs up claims that the six-core processors are the reason why you can't use Coffee Lake-S processors with older motherboards. The new chips require trace optimizations for power delivery so Intel decided to not offer intercompatibility between the products to ensure Coffee Lake is used on the right platform.