Something I've noticed is a fair amount of rotation for the country of printing over the last year or so. I'd hazard a guess that Mongoose are constantly on the lookout for the best deal around to print any given book.
As a consumer as well as a retailer, it's nice to know they're doing their best to keep prices stable, while other publishers might have chosen to stick with a single printing firm and just let their prices rise up when necessary. Having said that, it is a little irritating when you've been used to seeing just about every hardback rulebook come out in glossy colour to suddenly find one in black and white. I can only guess this is down to an economics thing involving many factors including current printing prices, demand at the various print companies, the amount of line art in the product, and expected demand (the cost per copy of 100,000 glossy colour hardbacks can be cheaper than 5,000 black and white hardbacks)