Featured status expiration date

field “Set the number of days after which a listing loses featured status.” is optional.
Whad happend if it will be empty.
Featured status expiration date will be same with ad Expiration Date ?

No, the Expiration Date does not affect on featured status. If Featuring Date is not set then the listing will save featured status even if the listing is expired

This complicates matters. :frowning: Featuring should therefore be defined separately for each package.

Sorry for the confusion, the Featured Date itself affects the featured status - if you set a custom date there and check the Featured option, then the listing will lose the Featured status when this date is reached.
The Expiration Date affects the listing visibility, when the expiration date is reached the listing status is switched to Draft automatically.

What about advertisements fetured by default (checkbox ), of the premium type ?

The functionality is the same, if the Featured option is checked for a listing but the Featured Date is not set then the listing is featured forever, but if there’s a date (usually it’s set via the Paid Listings extension automatically) then the listing will lose its featured status on this date.