We still have a lot of work to do. We want to keep both versions running as much as possible, for testing, but also so that people can get used to it.
So there's no deadline for the eventual launch, but we still have a ways to go. I would rather not even try to give an estimate just because so much is still up in the air. Every time we run a test though, we get closer to a finished product.
Going forward, there will be periods of a few days to a week where we keep it open for people to play around with, followed by periods of downtime lasting a few days while we fix the bugs that came up previously.
So for now, I'd encourage everyone to feel free to use it as much as they can. The more you use it now, the easier the transition will be when it finally arrives 
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