eBay is experimenting with displaying actual estimated dates for customers' deliveries, rather than expressing them in numbers of days.
Using information on a consignment's dispatch date and delivery method provided by sellers, it is now specifying a window of dates during which goods can be expected to arrive.
In addition, eBay is showing the ETA information to sellers, and using it as an opportunity to try to persuade them to upgrade to an express delivery service, by showing a comparative expected arrival date if this premium option is chosen.
This removes some confusion surrounding eBay's definition of 'working days', and has been welcomed by many sellers as a result.
As yet, the facility is only being tried on certain listings, so you won't necessarily see the date range on your orders.
But it's expected that eBay will evaluate the effects of using both the specified dates and the existing timescale measures before settling on a preferred option.