The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
Date has passed, but hexus.net does not confirm it happened then; unverified.
Wikipedia's GDDR6 article says "The finalized specification was published by JEDEC in July 2017", GDDR6 offers "up to 16 Gbit/s" per pin at "1.35 V", and "Micron began mass production of 8 Gb chips in June 2018".
WCCFTech could not be fetched (403 error), but its own headline and 25 December 2017 publish date report Micron "completing GDDR6 design and qualification" with mass production targeted for the first half of 2018 - consistent with the pin's stored 31 March 2018 date marking that Q1 2018 target.
PCPer reports Micron's own disclosure that it "expects to begin mass production of GDDR6 chips in early 2018" after pushing GDDR5X to 16Gbps, published 5 June 2017 - well ahead of, but consistent with, the pin's stored 31 March 2018 target date.
Something missing or wrong? Say it in your own words: a link that backs this pin up, a different start or end date and why, or a fact it lacks or gets wrong. The AI checks it against this pin's sources, searches for better ones, and adds any page that backs you up. The pin's own sources still count most.