They’ll be ”restored to a character immediately” except in the case of a disenchanted item which will need a ”review by Customer Support” before getting restored. Limited use.
Sorry but you can’t go spamming the new restore item feature. It’s only useable once every 30 days with accounts in good standing. Blizzard continues to urge caution with items.
”With this new self-service option the recovery of an item or items that were recently deleted or sold to a vendor can be restored to a character immediately when using the ticket submission system on our support site,” explained Blizzard.
”For any items that were accidentally disenchanted the same method can be used to request a review by Customer Support for restoration.”
”This restoration option may only be used once every 30 days on active World of Warcraft accounts that are in good standing. As this option has a limited availability and use, we still encourage caution when selling, deleting or disenchanting items.” For more information visit the official Battle.net website.