We'll admit there have been numerous setbacks, delays, and false starts, but we've been making rapid, daily progress on it for several months now; however, we can't realistically project a target completion date. It will be done when it's actually done, and we'd rather have it done right and well, vs. done poorly just to meet some arbitrary deadline. There's a maxim in development, "Good, Fast, and Cheap: Pick any two." We and our clientele demand it must be Good, and our pricing model means it has to be done Cheap (i.e., with the in-house developers we can afford to hire), so this unfortunately means it cannot be done Fast.
I can confirm I've already built the HTML/CSS for all but a few screens by now, and the experienced new developer we hired this spring is doing the JS/PHP programming necessary to make them actually functional. Initially, we're just going for feature-equivalence with our current Admin, to keep the project scope focused and avoid feature creep that would set things back even further. That said, the new UI architecture makes it readily extensible and flexible in a way the current Flash-based Admin never really was, so once it goes live to replace the current Admin, we'll then be able to start adding new features and functionality with relative ease.