Before I begin, the report comes from DigiTimes and they cite anonymous sources for this story. As always, a grain of salt is required when dealing with this level of alleged leak.
That out of the way, rumor has it that Apple's A11 SoC has been taped out on TSMC's 10nm process node. This is still a little way's away from production, however. From here, TSMC should be providing samples of the now finalized chip in Q1 2017, start production a few months later, and land in iOS devices somewhere in Q3/Q4. Knowing Apple, that will probably align with their usual release schedule — around September.
DigiTimes also reports that Apple will likely make their split-production idea a recurring habit. Currently, the A9 processor is fabricated at TSMC and Samsung on two different process nodes (16nm for TSMC and 14nm for Samsung). They claim that two-thirds of A11 chips will come from TSMC.