to GM and CM

GM lest any new items. but how to use old items to make new items. and old items could be useful.
if there are new items, many of which will sell old items, so that people think the server will be closed.

GM, no problem if there is a new item. but how long an item the user.
if the old items can be upgraded to the new item is better. to do system upgrades, old items are still functioning. so the GM can add the item upgrade