Can't seem to find much, from wikipedia
On 1 June 1999, John Benson was appointed as Wigan's manager. As Wigan settled into their new home at the JJB Stadium, Benson's side went 26 league games undefeated, before losing at home to Oldham Athletic on 7 January 2000, Benson picking up 2 Manager...
More like the Ipswich way... 3 times in 17 seasons this century has a team been first to 50 points and failed to go up, twice Ipswich - although the worst collapse is Burnley in 2001-02, from 50 points after 25 games to 75 after 46 and missing out on the play-offs :(
but do it in 24 games or...