Intel has been reporting that their 14nm lines are running at peak capacity but demand has been so strong that they cannot increase it any more.
Part of the problem is with the move to 14nm for chipsets has resulted in some problems with CPU production. The problems at 10nm have resulted in more demand for 14nm hardware.
Intel has also added more chipset models to the mix which has led to more shortgages. Shortages of the budget H310 PCH chips have forced motherboard makers to buy B360 PCH chips at higher cost. The supply of H370 and Q370 PCH chips are also limited.
The Z370 was launched at 22nm last October but with Coffee Lake, Intel changed all that to 14nm which is one of the reasons for the shortages. Intel pretty much has all their 14bm lines woking at capacity.
Intel suggested it may take until July 2018 to get caught up with backordered hardware. Intel also mentioned that 10nm is now pushed back to 2019 as yields continue to be well below production requirements. Sure 10nm will help eliminate much of the demand for 14nm hardware but Intel cannot do much about it yet.
Intel did say that yields are slowly improving but the pace of improvement is slower than they expected. The CEO Krzanich would not clarify any specific dates.