From the interview I recently did with David R. George III
for TrekCore.com (in which he confirms that the "Lost Era" to which he refers is in fact the one that had previously been titled "The Lost Era"), he also had this little tidbit to offer:
David R. George III wrote:
[...] my favorite series or time period to write happens to be whatever one I’m writing. [...] At the moment, I am very much into the time period 2303-2319.