If the 49ers wanted to remove the interim title from Coach Singletary they will have to wait until after the season to offer him a contract. The 49ers are forbid to sign Singletary anytime sooner. Why might you ask, well it is because of the Rooney Rule.
The rule states that a “club may name an interim from its staff without going through a formal interviewing process. However, the club must follow the mandatory interviewing process in choosing a new permanent head coach. No club may make a commitment to a coach retained during the season that extends beyond the end of the club’s playing season. Any contract that seeks to make such a commitment will not be approved.”
So the 49ers have to wait until after the season to hire Singletary, a minority, because the Rooney Rule requires them to interview a minority candidate before hiring a head coach. Yes even if that interim head coach is a minority.