I had a similiar problem when the item which I purchased was removed next day by the seller. However, the seller shipped the item, but never provided me shipping detail.
After the maximum dispatch duration (Ship before date), ebay will automatically initiate a refund claim to you. If the seller never shipped your item, the refund will proceed as normal. If he has shipped the item, but didn't entered the shipping details, the item will reach you, and the refund claim will be rejected.