They can go at any time especially if it's a popular item/rebate. The manufacture sets the limits once it's reached it's gone. It doesn't matter if it has an expiration date or not.
On most offers you will see a time stamp of when the item / offer will expire. The exceptions to the best of my knowledge would be an quantity limit or popular item. Ie the 2020 Thanksgiving dinner. I hope this helps you plan your next shopping trip.
Y'all be good