All sellers are required to have a minimum 5-day listing for highly faked brands. Ebay changed that policy at least 5 years ago in order to avoid sellers who'd run 1-day (and 3-day) listings and the items would end before they were reported.
If what you're saying is happening, it's probably that the sellers are running 3-day listings without brand name references and revising those listings and adding the brand names toward the end of the listing period. And it's not ebay-legal.
shopaholism said:^While there are other sites you could sell them on (Bonz or HardlyEverWornIt), neither of them get much traffic. You might try scrambling the name by listing them as "Isabel (Style name, size, color) Shoes Marant" and see if you can get them up that way.