From the number of emails I receive asking whether I still have particular items, despite having a BG (been and gone) code against that item for years, I assume that some people have difficulty translating the "availability codes" into their own language. I hope that this really simple explanation of the codes may help.
PO - Pre Order
MTH builds to predicted demand. As MTH announces various models that are expected to be produced the item will receive the "PO" code to show that the item may be ordered but that it has probably not been produced yet and is therefore not available for immediate delivery. Please also understand that the predicted availability date that MTH publishes can often be subject to delays, usually some months but in certain cases in excess of a year. I understand how annoying this is but MTH is not the only culprit here, delayed production is rife in the model railroad business.
AO - Available to Order
The model has been produced, although I do not expect to have it on my shelves it should be a simple matter to obtain one or more from MTH.
BC - Book Closed
The model is set for production but the order book has been closed, the order quantity has already reached the intended production run. It may just be worth a query in case there have been cancellations.
BG - Been and Gone
The model has been produced but I do not have it on my shelves and it has sold out at MTH also. A search of other dealers might turn one up but there are no guarantees.
CA - Cancelled
Not every model proposed for production is actually produced, if there is insufficient dealer/customer interest then items can be cancelled. Cancelled items can not be delivered. Although it is disappointing to see production plans cancelled it should be pointed out that MTH is far better than many manufacturers in eventually producing models that have been announced.
IS - In Stock
The model has been produced and it implies that I have at least one example on my shelf. If my in-stock indication is not accurate then by implication I can still obtain the item from MTH.
LS - Limited Stock
The model has been produced and it implies that I have at least one example on my shelf. If my in-stock indication is not accurate then by implication I would not expect to obtain fresh supplies from MTH.
RKC - RailKing Club
This indicates a model that was produced as the annual RailKing Club model for that particular product line. It is sometimes possible to obtain previous years offerings as dealer orderable items but this cannot be guaranteed.
DAP - Dealer Appreciation Program
This refers to the very limited availability items where a dealer might be limited to perhaps just two of a very small range of models. Some of these, because of the rarity, immediately aquire a premium collector value. I am often able to help out with these as long as they are ordered in good time.