If a category X is deleted, the items in it are transferred to a replacement category Y.
If, during the 6 months following this deletion, an item is put up for sale via the API, the Lister or EasyUploader using the deactivated category number X, it will automatically be transferred to the replacement category Y.
After this period, it will only be possible to put the item up for sale in the replacement category Y.
Sellers using the API, Lister or EasyUploader are strongly recommended to adapt their files to the replacement categories.
Removed categories will be announced in the articles of this "Category News" section.

You can find the numbers of all active categories via this link:  https://www.delcampe.net/en_GB/collectables/category-id