...
Introduce an optional field in the product form “Image Publish Date” which allows the manufacturer to select a date in future (not later than 12 months from current date).
...
By default the selected date is the date one which the product is being created. It can be overridden by clicking on the checkbox next to it.
...
In the public product page show images if there is no schedule date provided or schedule date has been met.
If schedule date has been set, then in the public product page show a warning message “Images will be published for public on <schedule date>”
...