Intel has not been able to keep up with demand for Coffee Lake i5 and i7 processors.
At present Intel is making the Core i7-8700K, Core i7-8700, Core i5-8600K, Core i5-8400 and other models in their Malaysian factory.
Prices for the i7-8700K is much higher than the MSRP. The i5-860K is also well above the MSRP.
To cope, Intel is now adding more supply with their Chengdu, China factory. Production is expected to reach the market by December 15, 2017.
Intel has to not only make wafers, the processors also have to be tested for speed and dissipated power etc. This can affect production depending on the relatively quality of the wafer yields.
Intel has been expanding 14nm production for 3 years and they should be able to get enough processors to market fairly quickly.
Intel promises that with the addition of the Chinese assembly & test lines, supply of tray versions of the six-core Coffee Lake CPUs will be more continuous. As a result, supply and demand for boxed versions of the said chips will likely get more balanced too.