There is no such thing as a former saint. Once a saint, always a saint. One cannot be 'decanonized.' There are a few saints who have been removed from the Calendar of Saints for various reasons but, in most cases, their cults are still allowed. All are still considered as saints. None of them were canonized so, officially, were never saints to begin with. Here are a few examples:
Saint Valentine of Rome
Saint Christopher
Saint Barbara
Saint Ursula
Saint Dorothy
Saint Philomena
Archie Manning, former Quarterback of the New Orleans Saints.
It has always been the "New Orleans Saints".
T.J. Slaughter played with the Saints in 2005 and with the 49ers in 2006.
Peyton and Eli Manning, and their father is Archie Manning, a former saint.
Danny Wuerffel
Archie Manning, former Quarterback of the New Orleans Saints.
Northwestern State University
Eli Manning
Matt Leinart is with the Cardinals,Reggie Bush is with the Saints,And Carson Palmer is on the Bengals.
Former Packers and current Saints cornerback Mike McKenzie attended the University of Memphis.
Eli and Peyton Manning are brothers and their father is Archie Manning.
St. Paul was originally Saul of Tarsus, who hated Christians and wanted them all imprisoned (or worse). After his conversion on the road to Damascus, Saul adopted the name Paul, to show a change from his former life.