Retro Fighters just posted an update on their Kickstarter page. In it they state that the initial samples are finished and wish to get the prototypes into a test batch production run. If the pilot production and final set of testing is successful. Mass production will soon follow. Retro Fighters had hoped to have these controllers finished and out to backers in September, but stated they ran into a few quality issues. The new target window for delivery to backers is set to be in December/January.
Links: Kick Starter Update Post – https://www.kickstarter.com/projects/1247448559/next-gen-dreamcast-controller/posts/2675021
Kick Starter Update Post Timeline – https://www.kickstarter.com/projects/1247448559/next-gen-dreamcast-controller/posts/2604070