Up until now, the Armada Wars paperbacks have been available in two editions: the standard edition, and the cheaper "compressed" edition.
The thinking here is now... nobody wants to pay more for the same book. The last two novels will be prohibitively expensive at the 12-point text size anyway, and having just one edition will simplify matters.
The larger, more expensive paperbacks will therefore be vanishing next month. If you want copies, the time to buy them is now!