Tapeout to samples:
40nm, 28nm - 8 weeks
20nm - 4-5 months
Prove me wrong.
Maybe KnC have very good relations and they can get it faster. They do chips for 10 years. Can't be all in vain.
KnC has boat load of money from self-mining and it is in their best interest to pay whatever extra expedite fee to get the process shorten so they can self-mine sooner (time = money in bitcoin mining). And it is also in TSMC's best interest to produce the new 20nm wafer at faster and faster pace, time is also money in their business. The less time it takes, the more 20nm wafers they can make for other customers = more money. Besides, what better marketing for more 20nm business if they can tell their other potential customers they have gotten the 20nm manufacturing time down to 8 weeks or less.