(b) Any person who for reasons other than retirement or death ceases to be a group I teacher or political subdivision employee prior to attaining the age of 60, and who[,] was eligible to retire as of July 1, 2008[, receives] and retired on or before July 1, 2009 with a vested deferred retirement allowance, and who has completed no less than 20 years of group I creditable service by July 1, 2008 a