To make sure when your item is going to ship, first make sure to re-check the item's description. Normally all the information regarding pre-orders is written there. If something changes it'll be modified to be seen publicly independently, in each item's description box, so we highly recommend checking back from time to time.
We don't always have full details of the items for Pre-Order. Normally, the estimated arrival date is accurate. However, it’s not uncommon for manufacturers to miss delivery dates and, for that reason, estimated time of arrival is not always secured. The factory may encounter all kinds of problems during development and production, but if that's the case you'll be notified.