More generally, tick–tock is an engineering model which refreshes one half of a binary system each release cycle.
In March 2016, Intel announced in a Form 10-K report that it would always do this in future, deprecating the tick–tock cycle in favor of a three-step process–architecture–optimization model, under which three generations of processors are produced under a single manufacturing process, with the third generation out of three focusing on optimization.
With Silvermont Intel tried to start Tick-Tock in Atom architecture but problems with the 10 nm process did not allow to do this.
There is no official confirmation that Intel uses Process-Architecture-Optimization for Atom but it allows us to understand what changes happened in each generation.
[70] In 2018, Intel announced that Knights Landing and all further Xeon Phi CPU models were discontinued.