I'm not sure why everyone on MR is so set on a 12 month cycle. First of all, it is a very passive pattern. slows innovation. lets the competition heat up. delays new products. etc. And secondly, the only precedent is the iPhone. iPods didn't even switch to a yearly cycle until their 8th gen iPod, and even then some of the updates have been unreliable. In fact even the iPhone got a storage bump halfway through the first year. The iPhone makes sense to have a reliable upgrade timeframe due to carrier contracts. The iPad is under no such obligation.
You have no clue about design, engineering, and production cycles. Adding every new feature as it is developed involves massive changes in redesign, reengineering, and retooling production lines.
I am actually shocked Apple can come out with a new iPhone or iPad on a 12 month cycle.