Kool-Aid McKinstry switching to 4th number in 3 years with the Saints
Corroborated by 3 sources from 3 publishers
TL;DR
Reports differ across sources; according to sports.yahoo.com, matt Leinart: USC asked me to unretire my jersey for a recruit, I said absolutely not "When I was at USC, I got my number retired," Leinart said on his Throwbacks Podcast.
Sources
1
Yahoo Sports
https://sports.yahoo.com/articles/kool-aid-mckinstry-switching-4th-225732145.html
2
Yahoo Sports
https://sports.yahoo.com/articles/why-purdues-braden-smith-wore-205134642.html
3
Yahoo Sports NFL
https://sports.yahoo.com/articles/luke-gifford-plans-dre-greenlaw-183000999.html
4
Yahoo Sports
https://sports.yahoo.com/articles/matt-leinart-usc-asked-unretire-094001669.html
5
CBS Sports
https://www.cbssports.com/college-football/news/matt-leinart-usc-unretire-jersey
6
Fox News Sports
https://www.foxnews.com/sports/usc-legend-says-hes-given-school-officials-strong-answer-whether-hed-unretire-number-recruits