What’s the skinny on the new signs and ownership change at the 17th St. Cafe at 1610 Montana Ave. in Santa Monica?  After opening and developing the cafe for 14 years, owner Jack Srebnik sold it in 2003.  Since then, however, the reviews of the Montana Ave. institution have been, well let’s just say less than stellar.  So it appears that Jack is back.  He’s buying it back from the current owners under the auspices of his partnership in Beverly Bagels Inc.  Rather than trying to reconstitute the tainted 17th St. Cafe brand, he is changing the name to Jack’s on Montana.  Expect a menu of brunch, salads, and sandwiches similar to the one that made the cafe a popular breakfast and lunch spot with locals for years.