According to the FOX network for next week, the week of October 6th, the 30th Anniversary Reunion Special will indeed be repeating on Monday, October 7th on FOX at 8:00PM.>
However, there are two little notes at the bottom, the first one says that “Boston Public” will be pre-empted that night, and the second states that “MLB Division Playoff game 5 may air tonight instead.” There is a chance the Reunion Special may not air, if this MLB game 5 needs to air instead.
Source: FOX.com