Those pieces are set to come in the next period of time, be it a quarter, or whatever. Now, you make the remainder of your payment. Sounds reasonable for an independent watchmaker making a piece to order. Now, that's what an FPJ is and we may not quite be used to that.
Because it slides so neatly up a shirt cuff and due to the Frodsham team's goal of making it very reliable (you may recall one prototype was worn on daily bike commutes, the other worn while mowing the lawn, etc), I've discretely worn it quite a bit.