I'm missing 4 ships in total from over the last 3 months. What's really weird is that they keep telling me "on back-order" whenever I call. I was in the first group of American pre-ordered subscriptions from before the series started shipping and am located in one of the states where they are warehousing and shipping to American subscribers from (Pennsylvania) and because of that I have to pay state sales-tax too. Shouldn't they have manufactured more than the subscriber number? They have a literal number that should technically be a minimum manufacturing number. Shouldn't that theoretically mean that I'm first subscribed, first served and if I don't get a ship from my subscription, no American being shipped from the PA warehouse does?
PA represent! My story is much the same as yours. Early subscriber, in at the beginning. I got fed up with my shipments being late and "not-in-stock" while my local comic book store kept getting the SAME ships reliably, at least a week or two before my shipments came - often earlier.
So I cancelled my subscription and started pre-ordering through my local retailer using Diamond's "Previews" catalog. There were a couple hiccups during the transition (because you pre-order 2-3 months in advance, and I had neglected to start ordering before I cancelled my subscription because I did it spur-of-the-moment out of frustration), but since the ships I pre-ordered have started to come in, I've received everything on time - and apparently shipped with greater care than my UPS delivery guy does.
I've been trying to get an Eaglemoss Second Doctor figurine for almost a year, too. Never in stock at their store. The American store is absolute CRAP about restocking.